Retired Vice Adm. Elton W. (Joe) Grenfell, 76, a much-decorated officer and the only man to have commanded both the Pacific and Atlantic submarine fleets, died Thursday at his Alexandria home after a stroke.

Known as the "enlisted man's admiral," he spent 23 years of his military service in submarines, longer than any other Navy officer.

As a lieutenant commander in April 1941, he assumed command of the USS Gudgeon, the first submarine to go on war patrol from Pearl Harbor after the Japanese attack on the fleet on Dec. 7, 1941.

Adm. Grenfell received the Navy Cross and the Silver Star as commanding officer of the Gudgeon, which also was the first U.S. submarine credited with sinking an enemy submarine and a Japanese combatant ship, as well as two Japanese transports.

In 1942, while returning to Pearl Harbor after receiving the Navy Cross from President Roosevelt, Adm. Grenfell was injured in an airplane crash and detached from active duty.

He then was assigned to the staff of the commander of the Submarine Force of the Pacific Fleet as strategic planning officer. He received the Legion of Merit for planning and coordinating submarine attacks in enemy waters.

In 1944 and 1945 he served as commander of the Pacific Fleet's submarine Division 44 and Submarine Squadron 34, for which he was awarded a Gold Star in lieu of a second Legion of Merit.

After the war, Adm. Grenfell was assigned to the Department of the Navy here as assistant deputy for undersea warfare in the submarines division.

From 1949 to 1951, he was chief of staff to the Pacific Fleet's submarine Force. In 1956, after several assignments with the Office of the Chief of Naval Operations, he assumed command of the Pacific Fleet's Submarine Force.

In 1960 he was named commander of the Atlantic Fleet's Submarine Force, also serving as submarine operations adviser for Polaris operations. He received the Distinguished Service Medal when he retired in 1964.

Following his military retirement Adm. Grenfell worked as a consultant to private industry on deep sea rescue, oceanography and undersea warfare.

He was born in Fall River, Mass., and graduated from the Naval Academy at Annapolis. He earned a master's degree in mechanical engineering from the University of California at Berkeley

In 1961 Adm. Grenfell established the Dolphin Scholarship Foundation for the children of Navy submarine personnel.

Survivors include his wife, the former Martha F. Lindsey of Alexandria; a son, Stephen J. F. Grenfell of Baltimore; two daughters, Mrs. Thomas O. Duffey of Honolulu and Elizabeth Anne Greenfell of Melbourne; two stepchildren, Navy Capt. E. E. Lindsey of Norfolk, and Mrs. N. F. Colby of Stuttgart, West Germany, and 11 grandchildren.

The family suggests that expressions of sympathy be in the form of contributions to the Dolphin Scholarship Foundation in Norfolk.