Edwin F. Sweetser, 69, a retired official of the Defense Department's missile research and development program, died of cancer Sunday at Suburban Hospital in Bethesda.

Mr. Sweetser joined the Pentagon in 1947 as a deputy director for guided missiles on the Research and Development Board. He was executive secretary of an ordnance committee in the Office of the Assistant Secretary of Defense for Research and Development in the 1950s.

He was director of the Office of Guided Missiles for two years before becoming a special assistant to the director of Defense Research and Engineering in 1961. He retired in 1970.

Mr. Sweetser was born in Colima, Mexico, and moved to Albany, N.Y., at an early age, He was a 1933 graduate of Tufts University, where he earned a bachelor's degree in electrical engineering. He later did graduate work in radar engineering at Harvard University and the Massachusetts Institute of Technology.

He came to Washington in 1942 during World War II duty as a Navy commander. After the war, he worked for the Johns Hopkins University Applied Physics Laboratory before joing the Defense Department.

Mr. Sweetser was a member of the American Ordnance Association, the Pentagon Officers Athletic Club, and the Kenwood Golf and Country Club.

He is survived by his wife, Irma, of the home in Bethesda; a son, Perry, of Vienna, Austria, two daughters, Barbara Frederick, of Bethesda, and Catherine, of Washington; his mother Adelina S. Sweetser, and a sister, Helen Seay, both of Albany; two other sisters, Adelina Johnson, of Washington, and Ruth Hapgood, of Lynchburg, Va., and two grandchildren.

The family suggests that expressions of sympathy be in the form of contributions to the Centers for the Handicapped, 10501 New Hampshire Ave., Silver Spring.