Andrew F. Oehmann, 70, a Washington lawyer who had served with the Federal Reserve Board and the Justice Department, died at Suburban Hospital in Bethesda Thursday after a heart attack. He was stricken while playing golf at the Kenwood Country Club.

At the time of his death, Mr. Oehmann was counsel to the law firm of Moore, Foster and Oehmann. Earlier, after retiring in 1975 as acting general counsel of the Federal Reserve Board, he had been counsel to the firm of Miller, Cassidy, Larroca and Lewin. He lived in Washington.

Mr. Oehmann was born in Washington. He graduated from Eastern High School, where he was captain of the football team.He attended Georgetown University's Foreign Service School and graduated from its law school in 1938. He also earned a degree from the Benjamin Franklin School of Accounting.

He joined the criminal division of the Justice Department in 1941, then interrupted his legal career to serve with the Navy in World War II, and saw duty in the Mediterranean.

After the war, Mr. Oehmann was appointed an assistant US.. attorney for the District of Columbia. From 1950 to 1958, he was a special assistant to the assistant attorney general in charge of the criminal division at Justice, and later first assistant to the assistant attorney general in charge of the tax division.

He left Justice in 1958 to practice with the law firm of Dow, Lohnes and Albertson then returned to Justice in 1961 as executive assistant to Attorney General Robert F. Kennedy. He was Mr. Kennedy's representative on the board of directors of General Analine and Film Co. during that company's return to pulic control. The assets of the German company had been seized by the United States during World War Ii.

Mr. Oehmann returned to private practice in 1964. He maintained his own firm and was a director of the Admiral Corporation until joining the legal staff of the Federal Reserve Board in 1972.

He had served during 1972-78 as a member of the board of trustees of the D.C. Public Defender System. He was a member of the D.C. and Federal bar associations, the National Lawyers Club and the Army-Navy and Kenwood country clubs. He belonged to Our Lady of Victory Catholic parish.

His wife, Shirley, died in 1956.

He is survived by two daughters, Mary Ann Marton of Barnsville, Md., and Deborah Brashears of Rockville; two sons, Andrew F. Jr., of Bethesda, and Michael of Washington and three grandchildren.

The family suggests that expressions of sympathy be in the form of contributions to Our Lady of Victory School.