William O. Hall, 63, a retired director general of the Foreign Service and a former ambassador to Ethopia, died Tuesday in a Portland, Ore., hospital of complications following kidney surgery.

Mr. Hall's career with the federal government spanned 33 years. He began working for the U.S. Bureau of the Budget in 1940. He served in the Navy during World War II and joined the State Department in 1974. He retired in 1973.

His assigments were numerous and various. In 1952, he was named deputy U.S. representative and senior adviser to the U.S. mission to the United Nation. While there, he also served as a member of the General Assembly's advisor committee on administrative budgetery questions.

Mr. Hall was assigned to the U.S. Embassy in London.

Other posts included assistant administrator for the U.S. Agency for International Development, consul general and deputy chief of mission for the U.S. Embassy in Karachi, pakistan, member of the U.S. delegation to the Geneva Conference on Peaceful Uess of Atomic Energy, and deputy assistant secretary of State for budget and finance.

In 1967, Mr. Hall was sworn in as U.S. ambassador to Ethiopia. He served as ambassador until 1971, when he was named director general of the Foreign Service. He retired in 1973. In 1966, he receive the Career Service Award of the National Civil Service League.

Born in Roswell, N.M., Mr. Hall grew up in Portland, and graduated from the University of Oregon.

After retirement, Mr. Hall returned to Portland and became active in community affairs, including service as director of the YMCA.

Survivors include his wife Jayne, of the home, two sons, William Jay of Achorage, Alaska, and Robert Barnard, of Washington; a daughter, Sarah Booth Sternglanz, of Stony Brook, N.Y.; a brother, Barnard of St. Paul, Minn and two grandchildren.

The family suggests that expressions of sympathy be in the form of contributions to the American Foreign Service Scholarship Fund, the State Department, Washington, D.C.