UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D. C. 20549

FORM 10-K

For the fiscal year ended June 30, 2003

OR

For the transition period from                      to                     

Commission File No. 1-4982

PARKER-HANNIFIN CORPORATION

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code (216) 896-3000

Securities registered pursuant to Section 12(b) of the Act:

Securities registered pursuant to Section 12(g) of the Act:

None

Indicate by check mark whether the Registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the Registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.  Yes  x.  No  ¨.

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of Registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K  x.

Indicate by check mark whether the Registrant is an accelerated filer.  Yes x  No  ¨.

The approximate aggregate market value of the voting stock held by non-affiliates of the Registrant as of December 31, 2002, excluding, for purposes of this computation only, stock holdings of the Registrant’s Directors and Officers: $5,422,827,992.

The number of Common Shares outstanding on July 31, 2003 was 118,167,923.

DOCUMENTS INCORPORATED BY REFERENCE

Portions of the following documents are incorporated by reference:

PARKER-HANNIFIN CORPORATION

FORM 10-K

Fiscal Year Ended June 30, 2003

PART I

ITEM 1. Business. Parker-Hannifin Corporation is a leading worldwide full-line manufacturer of motion control products, including fluid power systems, electromechanical controls and related components. Fluid power involves the transfer and control of power through the medium of liquid, gas or air, in hydraulic, pneumatic and vacuum applications. Fluid power systems move and position materials, control machines, vehicles and equipment and improve industrial efficiency and productivity. Components of a simple fluid power system include a pump which generates pressure, valves which control the fluid’s flow, an actuator which translates the pressure in the fluid into mechanical energy, a filter to insure proper fluid condition and numerous hoses, couplings, fittings and seals. Electromechanical control involves the use of electronic components and systems to control motion and precisely locate or vary speed in automation applications. In addition to motion control products, the Company also is a leading worldwide producer of fluid purification, fluid control, process instrumentation, air conditioning, refrigeration, electromagnetic shielding and thermal management products and designs and manufactures custom-engineered buildings. Also, through Wynn Oil Company and its subsidiaries (the “Wynn’s Specialty Chemical Group”), the Company develops, manufactures and markets specialty chemical products and maintenance service equipment.

The Company was incorporated in Ohio in 1938. Its principal executive offices are located at 6035 Parkland Boulevard, Cleveland, Ohio 44124-4141, telephone (216) 896-3000. As used in this Report, unless the context otherwise requires, the term “Company” or “Parker” refers to Parker-Hannifin Corporation and its subsidiaries.

The Company’s investor relations internet website address is www.phstock.com. The Company makes available free of charge on or through its website its annual report on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, and any amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as soon as reasonably practicable after filing or furnishing such material electronically with the Securities and Exchange Commission.

The Company’s manufacturing, service, distribution and administrative facilities are located in 37 states and worldwide in 43 foreign countries. Its motion control technology is used in the products of its business Segments: Industrial; Aerospace; Climate & Industrial Controls; and Other. The products are sold as original and replacement equipment through product and distribution centers worldwide. The Company markets its products through its direct-sales employees, independent distributors, sales representatives and builder/dealers. Parker products are supplied to approximately 380,000 customers in virtually every significant manufacturing, transportation and processing industry. For the fiscal year ended June 30, 2003, net sales were $6,410,610,000; Industrial Segment products accounted for 69% of

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net sales, Aerospace Segment products for 17%, Climate & Industrial Controls Segment products for 11% and Other Segment products for 3%.

Markets

Motion control systems are used throughout industry in applications which include moving of materials, controlling machines, vehicles and equipment and positioning materials during the manufacturing process. Motion control systems contribute to the efficient use of energy and improve industrial productivity.

The approximately 380,000 customers who purchase the Company’s products are found throughout virtually every significant manufacturing, transportation and processing industry. No customer accounted for more than 4% of the Company’s total net sales for the fiscal year.

The major markets for products of the Fluid Connectors, Hydraulics, Automation and Seal Groups of the Industrial Segment are agricultural machinery, automotive, construction machinery, electronic equipment, fabricated metals, food production, industrial machinery, pulp and paper, machine tools, marine, medical equipment, mining, mobile equipment, chemicals, robotics, semi-conductor equipment, telecommunications, textiles, transportation and every other major production and processing industry. The major markets for products manufactured by the Instrumentation Group of the Industrial Segment are power generation, oil and gas exploration, petrochemical and chemical processing, pulp and paper, semi-conductor manufacturing, medical and analytical applications. The major markets for products of the Filtration Group of the Industrial Segment are industrial machinery, mobile equipment, diesel engines, process equipment, marine, aviation, environmental and semi-conductor manufacturing. Sales of Industrial Segment products are made to original equipment manufacturers and their replacement markets.

Aerospace Segment sales are made primarily to the commercial, military and general aviation markets and are made to original equipment manufacturers and to end users for maintenance, repair and overhaul.

The products manufactured by the Climate & Industrial Controls Segment are used principally in mobile air conditioning systems, industrial refrigeration systems, residential and commercial air conditioning systems and equipment and industrial fluid control markets. Sales of the Climate & Industrial Controls Segment are made to original equipment manufacturers and their replacement markets.

Astron Building Systems^® (“Astron”) of the Other Segment produces pre-engineered single and multi-story buildings that serve industries throughout Europe. The Wynn’s Specialty Chemical Group of the Other Segment develops and manufactures a wide variety of specialty chemical car care and industrial products that are marketed to automobile service technicians, consumers and industrial product users.

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Principal Products, Methods of Distribution and Competitive Conditions

Industrial Segment. The product lines of the Company’s Industrial Segment cover most of the components of motion control systems. The Fluid Connectors Group manufactures connectors, including tube fittings, hose fittings, valves, hoses and couplers, which control, transmit and contain fluid. The Hydraulics Group produces hydraulic components and systems for builders and users of industrial and mobile machinery and equipment, such as cylinders, accumulators, rotary actuators, valves, motors and pumps, hydrostatic steering units, power units, integrated hydraulic circuits, electrohydraulic systems, metering pumps and power take-off equipment. The Automation Group supplies pneumatic and electromechanical components and systems. Pneumatic products include pneumatic valves, air preparation units, pneumatic actuators, vacuum products, pneumatic logic systems, and structural extrusions. Electromechanical products include human-machine interface hardware and software; industrial PCs; single and multi-axis stand-alone and bus-based controllers; rotary and linear servo motors; rotary and linear stepper motors; analog and digital stepper and servo drives; precision gearheads, ballscrew, belt, and linear motor driven positioning tables; electric rod-style and rodless cylinders; and gantry robots. The Seal Group manufactures sealing devices, including o-rings and o-seals; gaskets and packings, which insure leak-proof connections; electromagnetic interference shielding; and thermal management products. The Filtration Group manufactures filters, systems and instruments to monitor and to remove contaminants from fuel, air, oil, water and other fluids and gases, including hydraulic, lubrication and coolant filters; process, chemical and microfiltration filters; compressed air and gas purification filters; lube oil and fuel filters; fuel conditioning filters; fuel filters/water separators; cabin air filters; intake air filters; and nitrogen and hydrogen generators and condition monitoring devices. The Instrumentation Group manufactures high quality critical flow components for process instrumentation, ultra-high-purity, medical and analytical applications, including fittings, valves, regulators and PTFE products.

Industrial Segment products include both standard items which are produced in large quantities and custom units which are engineered and produced to original equipment manufacturers’ specifications for application to a particular end product. Both standard and custom products are also used in the replacement of original motion control system components. Industrial Segment products are marketed primarily through field sales employees and more than 8,300 independent distributors.

Aerospace Segment. The principal products of the Company’s Aerospace Segment are hydraulic, fuel and pneumatic systems and components that are used on commercial and military airframe and engine programs.

The Aerospace Segment offers complete hydraulic and primary flight control systems that include hydraulic, electrohydraulic and electromechanical components used for precise control of aircraft rudders, elevators, ailerons and other aerodynamic control surfaces and utility hydraulic components such as reservoirs, accumulators, selector valves, electrohydraulic servovalves, thrust-reverser actuators, engine-driven pumps, motor pumps, nosewheel steering systems, electromechanical actuators, engine controls and electronic controllers. The Aerospace Segment also designs and manufactures aircraft wheels and brakes for the general aviation and military markets.

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The Aerospace fuel product line includes complete fuel systems as well as components such as fuel transfer and pressurization controls, in-flight refueling systems, fuel pumps and valves, fuel measurement and management systems and center of gravity controls, engine fuel injection atomization nozzles, manifolds and augmentor controls, and electronic monitoring computers.

Pneumatic components include bleed air control systems, pressure regulators, low-pressure pneumatic controls, heat transfer systems, engine start systems, engine bleed control and anti-ice systems, and electronic control and monitoring computers.

Aerospace Segment products are marketed by the Company’s regional sales organization and are sold directly to manufacturers and end users.

Climate & Industrial Controls Segment. The principal products of the Company’s Climate & Industrial Controls Segment are refrigeration and air conditioning systems and components and fluid control process systems and components for use primarily in the mobile and stationary refrigeration and air conditioning industry.

The Climate & Industrial Controls Segment manufactures components and systems for use in industrial, residential, commercial, automotive and mobile air conditioning and refrigeration systems and other applications, including pressure regulators, solenoid valves, expansion valves, filter-dryers, gerotors and hose assemblies. The Climate & Industrial Controls Segment products are marketed primarily through field sales employees and independent distributors and wholesalers.

Other Segment. The principal products of the Company’s Other Segment are custom-engineered buildings which are designed and manufactured by Astron; and automotive and industrial chemical products and professional automotive service equipment that are developed by the Wynn’s Specialty Chemical Group.

Astron’s pre-engineered single and multi-story buildings serve as factories, warehouses, aircraft hangars, indoor athletic facilities, automobile showrooms, offices and supermarkets. Astron’s custom-engineered buildings are marketed primarily through builder/dealers and field sales employees.

The Wynn’s Specialty Chemical Group’s product line includes professional chemical products, programs and equipment for automobile service technicians, automotive chemical products for consumers, and forging compounds, cleaners, release agents, lubricants, cutting and drawing fluids and multipurpose coolants used in precision metal forming and machining operations. Products are marketed primarily to consumers, automobile dealerships and other automotive service facilities, and industrial and manufacturing companies and are distributed through a strong network of independent distributors as well as a direct sales force.

Competition. All aspects of the Company’s business are highly competitive. No single manufacturer competes with respect to all products manufactured and sold by the Company and the degree of competition varies with different products. In the Industrial Segment, the Company competes on the basis of product quality and innovation, customer service, its manufacturing and distribution capability, and competitive price. The Company believes that, in most of the major markets for its

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Industrial Segment products, it is one of the principal suppliers of motion control systems and components. In the Aerospace Segment, the Company has developed alliances with key customers based on the Company’s advanced technological and engineering capabilities, superior performance in quality, delivery, and service, and price competitiveness, which has enabled the Company to obtain significant original equipment business on new aircraft programs for its systems and components and, thereby, obtain the follow-on repair and replacement business for these programs. The Company believes that it is one of the primary suppliers in the aerospace marketplace.

In the Climate & Industrial Controls Segment, the Company competes on the basis of product quality and innovation, customer service, its manufacturing and distribution capability, and competitive price. The Company believes that it is one of the principal suppliers in the climate and industrial controls marketplace.

In the Other Segment, the Company competes on the basis of product quality and performance, strong brand recognition (Wynn’s) and competitive price.

Research and Product Development

The Company continually researches the feasibility of new products through its development laboratories and testing facilities in many of its worldwide manufacturing locations. Its research and product development staff includes chemists, mechanical, electronic and electrical engineers and physicists.

Research and development costs relating to the development of new products or services and the improvement of existing products or services amounted to $122,710,000 in fiscal year 2003, $109,090,000 in fiscal year 2002 and $115,004,000 in fiscal 2001. Reimbursements of customer-sponsored research included in the total cost for each of the respective years were $29,561,000, $13,517,000 and $17,143,000.

Patents, Trademarks, Licenses

The Company owns a number of patents, trademarks and licenses related to its products and has exclusive and non-exclusive rights under patents owned by others. In addition, patent applications on certain products are now pending, although there can be no assurance that patents will be issued. The Company is not dependent to any material extent on any single patent or group of patents.

Backlog and Seasonal Nature of Business

The Company’s backlog at June 30, 2003 was approximately $1,803,091,000 and at June 30, 2002 was approximately $1,862,992,000. Approximately 81% of the Company’s backlog at June 30, 2003 is scheduled for delivery in the succeeding twelve months. The Company’s business generally is not seasonal in nature.

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Environmental Regulation

The Company is subject to federal, state and local laws and regulations designed to protect the environment and to regulate the discharge of materials into the environment. Among other environmental laws, the Company is subject to the federal “Superfund” law, under which the Company has been designated as a “potentially responsible party” and may be liable for cleanup costs associated with various waste sites, some of which are on the U.S. Environmental Protection Agency Superfund priority list.

As of June 30, 2003, the Company is involved in environmental remediation at 24 manufacturing facilities presently or formerly operated by the Company and has been named as a “potentially responsible party,” along with other companies, at three off-site waste disposal facilities and two regional Superfund sites.

The Company believes that its policies, practices and procedures are properly designed to prevent unreasonable risk of environmental damage and the consequent financial liability to the Company. Compliance with environmental laws and regulations requires continuing management effort and expenditures by the Company. Compliance with environmental laws and regulations has not had in the past, and, the Company believes, will not have in the future, material effects on the capital expenditures, earnings, or competitive position of the Company.

As of June 30, 2003, the Company has a reserve of $15,282,000 for environmental matters which are probable and reasonably estimable. This reserve is recorded based upon the best estimate of costs to be incurred in light of the progress made in determining the magnitude of remediation costs, the timing and extent of remedial actions required by governmental authorities and the amount of the Company’s liability in proportion to other responsible parties.

The Company’s estimated total liability for the above mentioned sites ranges from a minimum of $15,282,000 to a maximum of $44,177,000. The actual costs to be incurred by the Company will be dependent on final delineation of contamination, final determination of remedial action required, negotiations with federal and state agencies with respect to cleanup levels, changes in regulatory requirements, innovations in investigatory and remedial technology, effectiveness of remedial technologies employed, the ultimate ability to pay of the other responsible parties, and any insurance or third party recoveries.

Energy Matters and Sources and Availability of Raw Materials

The Company’s primary energy source for each of its business segments is electric power. While the Company cannot predict future costs of such electric power, the primary source for production of the required electric power will be coal from substantial, proven coal reserves available to electric utilities. The Company is subject to governmental regulations in regard to energy supplies both in the United States and elsewhere. To date the Company has not experienced any significant disruptions of its operations due to energy curtailments.

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Steel, brass, aluminum, elastomeric materials and chemicals are the principal raw materials used by the Company. These materials are available from numerous sources in quantities sufficient to meet the requirements of the Company.

Employees

The Company employed approximately 46,787 persons as of June 30, 2003, of whom approximately 19,899 were employed by foreign subsidiaries.

Business Segment Information

The net sales, segment operating income and identifiable assets by business segment and net sales and long-lived assets by geographic area for the past three fiscal years, as set forth on pages 13-11 to 13-12 of Exhibit 13 hereto, are incorporated herein by reference.

ITEM 1A. Executive Officers of the Company

The Company’s Executive Officers are as follows:

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Mr. Washkewicz was elected Chief Executive Officer effective in July 2001 and President in February 2000. He was Chief Operating Officer from February 2000 to July 2001; and Vice President and President of the Hydraulics Group from October 1997 to February 2000.

Mr. Myslenski was named Senior Vice President in August 2002 and was elected Operating Officer effective in October 2001. He was a Corporate Vice President from October 2001 to December 2002; Vice President, Operations from July 2001 to October 2001; Vice President from October 1997 to July 2001; and President of the Fluid Connectors Group from July 1997 to July 2001.

Mr. Vande Steeg was named Senior Vice President in August 2002 and was elected Operating Officer effective in January 2002. He was a Corporate Vice President from January 2002 to August 2002; Vice President from September 1995 to January 2002; and President of the Seal Group from 1987 to January 2002.

Mr. Pistell was elected as Vice President – Finance and Administration and Chief Financial Officer effective in April 2003. He was a Vice President from October 2001 to April 2003; and Treasurer from July 1993 to April 2003.

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Mr. Banks was elected as a Vice President in October 2001 and named President of the Instrumentation Group effective in July 2001. He was Vice President—Operations of the Climate & Industrial Controls Group from January 2001 to July 2001; and General Manager of the Skinner Valve Division from August 1997 to December 2000.

Mr. Barker was elected as a Vice President in April 2003 and named President of the Aerospace Group effective in March 2003. He was Vice President—Operations of the Aerospace Group from April 1996 to March 2003.

Mr. Bond was elected as a Vice President in July 2000 and named President of the Automation Group effective in April 2000. He was Vice President—Operations of the Fluid Connectors Group from July 1997 to April 2000.

Mr. Cortright was elected as a Vice President in January 1999 and named President of the Climate & Industrial Controls Group effective in November 1998. He was President of the Latin American Group from November 1987 to November 1998.

Mr. Dennis was elected as a Vice President in October 2001 and as Controller effective in July 1999. He was Vice President/Controller of the Automation Group from August 1997 to July 1999.

Mr. Droxner was elected as Vice President and named President of the Seal Group effective in January 2002. He was President of the Seal Group Europe from July 1999 to January 2002 and General Manager of the O-Ring Division Europe from October 1987 to July 1999.

Mr. Eline was elected as Vice President—Chief Information Officer effective in August 2002. He was Vice President—Information Technology International from July 2000 to August 2002 and Vice President—Enterprise Systems International from October 1987 to July 2000.

Mr. Hayes was elected a Vice President in April 1993. He was President of the Aerospace Group from April 1993 to March 2003.

Ms. Huggins was elected as a Vice President and Treasurer in April 2003. She was Vice President and Controller of the Filtration Group from June 2000 to April 2003 and Corporate Financial Services Manager from April 1996 to June 2000.

Mr. Kashkoush was elected as a Vice President in July 2000 and named President of the Hydraulics Group in February 2000. He was President of the European Operations of the Hydraulics Group from February 1999 to February 2000 and Group Vice President—Sales and Marketing of the Hydraulics Group from July 1997 to February 1999.

Mr. Mackie was elected as a Vice President in July 2000 and named President of the Fluid Connectors Group in July 2001. He was President of the Instrumentation Group from July 1997 to July 2001.

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Mr. Maxwell was elected as Vice President—Technology and Innovation in July 2003. He was Vice President—Engineering and Innovation from January 2003 to July 2003; Business Unit Manager of the Fluid Control Division from July 2002 to January 2003; and Engineering Manager of the Racor Division from July 1998 to July 2002.

Mr. Oelslager was elected as a Vice President in October 1997 and named President of the Filtration Group effective in March 2000. He was President of the Automation Group from July 1997 to March 2000.

ITEM 2. Properties. The following table sets forth the principal plants and other materially important properties of the Company and its subsidiaries. The leased properties are indicated with an asterisk. A “(1)” indicates that the property is occupied by the Company’s Industrial Segment, a “(2)” indicates that the property is occupied by the Company’s Aerospace Segment, a “(3)” indicates that the property is occupied by the Company’s Climate & Industrial Controls Segment, and a “(4)” indicates that the property is occupied by the Company’s Other Segment.

UNITED STATES

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The Company believes that its properties have been adequately maintained, are in good condition generally and are suitable and adequate for its business as presently conducted. The extent of utilization of the Company’s properties varies among its plants and from time to time. The Company’s restructuring efforts over the past several years have brought capacity levels closer to present and anticipated needs. Although capacity has been reduced over the last fiscal year, most of the Company’s material manufacturing facilities remain capable of handling additional volume increases.

ITEM 3. Legal Proceedings. None.

ITEM 4. Submission of Matters to a Vote of Security Holders. None.

PART II

ITEM 5. Market for the Registrant’s Common Equity and Related Stockholder Matters. As of July 31, 2003, the number of shareholders of record of the Company was 5,969 and the number of beneficial owners was approximately 51,000. Information regarding stock price and dividend information with respect to the Company’s common stock, as set forth on page 13-34 of Exhibit 13 hereto, is incorporated herein by reference.

ITEM 6. Selected Financial Data. The information set forth on page 13-37 of Exhibit 13 hereto is incorporated herein by reference.

ITEM 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations. The information set forth on pages 13-2 to 13-9 of Exhibit 13 hereto is incorporated herein by reference.

ITEM 7A. Quantitative and Qualitative Disclosures About Market Risk. The Company enters into forward exchange contracts, costless collar contracts and cross-currency swap agreements to reduce its exposure to fluctuations in related foreign currencies. The total value of open contracts and

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any risk to the Company as a result of these arrangements is not material to the Company’s financial position, liquidity or results of operations.

The Company’s debt portfolio contains variable rate debt, inherently exposing the Company to interest rate risk. The Company’s objective is to maintain a 60/40 mix between fixed rate and variable rate debt thereby limiting its exposure to changes in near term interest rates. The Company has entered into an interest rate swap agreement for a $200 million notional principal amount. The swap agreement converts a portion of the Company’s variable rate debt to a fixed rate through 2004. The agreement is with a major financial institution and the risk of loss is considered remote. The carrying and fair value of this agreement is not material to the Company’s financial position, liquidity or results of operations. A one hundred basis point increase in near term interest rates would increase annual interest expense on variable rate debt by approximately $3.0 million.

For further discussion see the Significant Accounting Policies Footnote on pages 13-15 to 13-18 of Exhibit 13 hereto and incorporated herein by reference.

ITEM 8. Financial Statements and Supplementary Data. The information set forth on pages 13-10 to 13-37 of Exhibit 13 hereto is incorporated herein by reference.

ITEM 9. Changes in and Disagreements with Accountants on Accounting and Financial Disclosure. Not applicable.

ITEM 9A. Controls and Procedures. The Company carried out an evaluation, under the supervision and with the participation of the Company’s management, including the Company’s principal executive officer and principal financial officer, of the effectiveness of the Company’s disclosure controls and procedures as of the end of the fourth fiscal quarter of fiscal year 2003. Based on this evaluation, the principal executive officer and principal financial officer, have concluded that the Company’s disclosure controls and procedures are effective in all material respects, to ensure that information required to be disclosed in the reports the Company files and submits under the Securities Exchange Act of 1934 is recorded, processed, summarized and reported within the time periods specified in the Securities and Exchange Commission’s rules and forms.

The Company periodically conducts an evaluation, under the supervision and with the participation of the Company’s management, including the Company’s principal executive officer and principal financial officer as well as the Company’s Audit Committee and independent auditors, of its internal controls and procedures. Other than a strengthening of pricing oversight controls, there have been no significant changes in the Company’s internal controls or in other factors that could significantly affect the Company’s internal controls subsequent to the date of the most recent evaluation.

PART III

ITEM 10. Directors and Executive Officers of the Registrant. Information required with respect to the Directors of the Company is set forth under the caption “Election of Directors” in the definitive Proxy Statement for the Company’s 2003 Annual Meeting of Shareholders to be held October 22, 2003 (“2003 Proxy Statement”) and is incorporated herein by reference. Information with respect to

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the executive officers of the Company is included in Part I hereof. The information set forth under the captions “Audit Committee Financial Expert” and “Audit Committee” in the 2003 Proxy Statement is incorporated herein by reference.

The Company has adopted a code of ethics that applies to its Chief Executive Officer, Chief Financial Officer and Controller. The Code of Ethics is posted on the Company’s investor relations internet website at www.phstock.com under the Corporate Governance page.

ITEM 11. Executive Compensation. The information set forth under the captions “Compensation of Directors” and “Executive Compensation” in the 2003 Proxy Statement is incorporated herein by reference.

ITEM 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters. The information set forth under the captions ““Change in Control” Severance Agreements with Officers” and “Principal Shareholders of the Corporation” in the 2003 Proxy Statement is incorporated herein by reference. The information set forth under the caption “Equity Compensation Plan Information” in the 2003 Proxy Statement is incorporated herein by reference.

ITEM 13. Certain Relationships and Related Transactions. The information set forth under the caption “Certain Relationships and Related Transactions” in the 2003 Proxy Statement is incorporated herein by reference.

ITEM 14. Principal Accountant Fees and Services. The information set forth under the captions “Audit Fees,” “Audit-Related Fees,” “Tax Fees,” “All Other Fees” and “Audit Committee Pre-Approval Policies and Procedures” in the 2003 Proxy Statement is incorporated herein by reference.

PART IV

ITEM 15. Exhibits, Financial Statement Schedules, and Reports on Form 8-K.

The financial statements and schedule listed in the accompanying Index to Consolidated Financial Statements and Schedules are filed or incorporated by reference as part of this Report.

The exhibits listed in the accompanying Exhibit Index and required by Item 601 of Regulation S-K (numbered in accordance with Item 601 of Regulation S-K) are filed, furnished or incorporated by reference as part of this Report.

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SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the Registrant has duly caused this Report to be signed on its behalf by the undersigned, thereunto duly authorized.

August 29, 2003

Pursuant to the requirements of the Securities Exchange Act of 1934, this Report has been signed below by the following persons on behalf of the registrant and in the capacities and on the date indicated.

Signature and Title

DUANE E. COLLINS, Chairman of the Board of Directors; DONALD E. WASHKEWICZ,

Chief Executive Officer and Director; DANA A. DENNIS, Principal Accounting Officer;

JOHN G. BREEN, Director; WILLIAM E. KASSLING, Director; ROBERT J. KOHLHEPP,

Director; PETER W. LIKINS, Director; GIULIO MAZZALUPI, Director;

KLAUS-PETER MÜLLER, Director; CANDY M. OBOURN, Director;

HECTOR R. ORTINO, Director; ALLAN L. RAYFIELD, Director;

WOLFGANG R. SCHMITT, Director; DEBRA L. STARNES, Director; and

DENNIS W. SULLIVAN, Director.

Date: August 29, 2003

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PARKER-HANNIFIN CORPORATION

INDEX TO CONSOLIDATED FINANCIAL STATEMENTS AND SCHEDULES

Individual financial statements and related applicable schedules for the Registrant (separately) have been omitted because the Registrant is primarily an operating company and its subsidiaries are considered to be totally-held.

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PARKER-HANNIFIN CORPORATION

SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS

FOR THE YEARS ENDED JUNE 30, 2001, 2002 and 2003

(Dollars in Thousands)

F-2

Exhibit Index

*Management contracts or compensatory plans or arrangements.

Shareholders may request a copy of any of the exhibits to this Annual Report on Form 10-K by writing to the Secretary, Parker-Hannifin Corporation, 6035 Parkland Boulevard, Cleveland, Ohio 44124-4141.