Selwyn Siegel, 54, a real estate broker and insurance salesman in Silver Spring who was active in service organizations, died Friday at Suburban Hospital in Bethesda following a heart attack.

Mr. Siegel was born in Brooklyn, N.Y., and grew up in Forest Hills, N.Y. He was a sergeant in the Army Medical Corps during World War II, and served in Europe. After the war, he returned to Forest Hills and later moved to Philadelphia, where he was a manufactuerers' representative in women's wear.

In 1960, he moved to this area and settled in Potomac. He continued to work as a manufacturers' representative until 1979. He them switched to real estate and insurance, working for the Finci-Newman Insurance Agency and the Columbus Mutual Life Insurance Company, both of which are in Silver Spring.

Earlier this year, Mr. Siegel won a special leadership award from the President's Club of Columbus Mutual.

Mr. Seigel was vice president and a member of the boards of both the Progress Club Inc. and the Progress Club Foundation Inc., which are philanthropic organizations. He was chairman of the entertainment committee of the Progress Club for many years.

He also was a member of the B'nai Israel Congregation in Rockville and had been active in behalf of the Hebrew Home for the Aged, now the Hebrew Home of Greater Washington, Children's Hospital National Medical Center and the National Children's Center.

Mr. Siegel belonged to Norbeck Country Club, where he was on the board of governors and was chairman of the entertainment committee.He was the club's golf champion in 1963.

Survivors include his wife, Janet of Potomac; five sons, Scot, of Las Vegas, and Gary, Eric, Marc and Drew, all of Potomac, and two sisters, Jean Schlossenberg of Rockville, and Miriam Altman of Woodland Hills, Calif.

The family suggests that expressions of sympathy be in the form of contributions to the Progress Club Foundation Inc., Rockville.