Leon Lewis a retired department of Labor division chief and an internationally recognized authority on occupational classification, died Sunday at the Veterans Administration Hospital here after a long illness. He was 62.

Mr. Lewis, who lived at 1830 Opalocka Dr., McLean played a key role in the development of the second and third editions of the "Dictonary of Occupational Titles," The dictionary provides descriptive information concerning most jobs in the American economy.

The occupational dictionary, whose fourth edition Mr. Lewis had helped plan for publication later this year, is widely used by public employment services, counselors educators, libraries, personnel officers and employers at large.

Born in Brooklyn N.Y., Mr. Lewis was educated in public schools in New Jersey and received a B.A. degree in chemistry from the City College of New York. After moving to the Washington area in the late 1930's he attended both George Washington and American unversities.

During World War II, Mr. Lewis worked with the War Manpower Commission and was primarily responsible for developing basic job infomration for such vital industries as synthetic rubber and heavy chemicals. Following the war, he advised many government agencies, the armed services, private corporations, and universities on occupational analysis.

He also counseled such countries as Japan, Canada and various nations in Western Europe, the Middle East, Africa and South America on the development of publications similar to the dictionary.

In 1975 Mr. Lewis retired as chief of the Division of Occuptional Analysis at the Department of Labor's U.S. Employment Service. At that time he received the department's Distinguished Career Service Award, having previously received a series of merit and honor awards within the department. After his retirement, he became a consultant on manpower porblems to major American corporations.

Mr. Lewis is survived by his wife of 39 years, Irene, of the family home in McLean; his daughter, Dr. Marilyn L. Renfield, of Falls Church; a sister, Anne Bleier, of Los Angeles; a brother, Nathan, of Williamsburg, Va.; and two grandchildren.

Expressions of sympathy may be in the form of contributions to the Oncology Department at the Veterans Administration Hospital in Washington, D.C., in care of Dr. John Minna, its director.