Benjamin W. (Ben) Denio, 55, who had served the Navy for more than 34 years, died Friday after a heart attack.

He was stricken while attending a farewell party at the Navy Security Station here where he had retired the day before as a civilian communications specialist.

Mr. Denio had worked as a civilian for the Navy since retiring here in 1965 with the rank of radioman chief.

Born in Miami, he grew up in New York. He entered the Navy in 1942 and was based as a radioman in the Panama Canal Zone in World War II.

After the war, Mr. Denio worked as a civilian for the Navy in New York, and attended St. John's University there.

He returned to military duty in 1947, and served at various bases in this wountry. He was stationed in Alaska just before coming here in 1964 for his final military assignment.

Mr. Denio was a member of the Fleet Reserve Association, Amvets, and the Elks.

He is survived by his wife, Madeline, of the home in Arlington; a daughter, Darlene Gulius, of Arlington; a son Air Force, Capt. William J., of Little Rock, Ark.; his mother, Mrs. William B. Denio, and two sisters, Ann Rose Denio and Jane Bitler, of Queens, N.Y., and three grandchildren.