Daniel Henry Schmidt, 69, a retired State Department aide, died Friday at George Washington University Hospital after a heart attack.

At the time of his retirement in 1977, he was a systems analysis officer on the management services staff in the office of the controller for operations.

Earlier, he had served in the division of personnel, supervision and management. He had started work with the State Department after coming here in 1937.

Born in New York City, Mr. Schmidt served with the U.S. Army as a major during World War II. He retired from the Army Reserves in 1968 with the rank of lieutenant colonel.

He earned a degree in business administration from American University in 1955.

Mr. Schmidt had been an active volunteer leader in the National Capital Area Council of the Boy Scouts since 1951. He was a Mason.

He is survived by his wife, Elizabeth G., of the home in Silver Spring; three children, Julia A. Carvalho, of Reston, Navy Lt. S.G. Edwin A., stationed in Japan, and Robert D., of Fairfax, a sister, Dorothy E. Butler, of River Edge, N.J., and four grandchildren.

The family suggests that expressions of sympathy may be in the form of contributions to the Heart Fund.