Retired Vice Adm. Bernard L. Austin, 77, who won two Navy Crosses in less than a month while commanding destroyers in the Pacific in World War II, died of a heart attack Tuesday, at the Bethesda Naval Medical Center. He had cancer.

Adm. Austin commanded a destroyer division off Bougainville in the Solomon Islands in November 1943. On the night of Nov. 1, he was credited with helping to sink five Japanese warships and damaging four others. On the night of Nov. 24, he helped sink four enemy warships and damage two others. He received a Navy Cross, the second highest award for bravery in the naval service, for each of these actions.

Earlier in the war, Adm. Austin commanded a destroyer that was credited with sinking a German submarine during the North African landings in 1942. In June 1944, he was on the staff of Adm. Chester W. Nimitz, commander of the U.S. Navy in the Pacific.

After the war, Adm. Austin served several tours of duty in Washington and took part in the Korean conflict. He was assistant chief of naval operations for operations and plans in the late 1950s, and in 1960 became president of the Naval War College. He held that post until his retirement in 1964.

Adm. Austin immediately was named presiding officer of the panel that investigated the loss of the submarine Thresher in 1963. He also served as chairman of the Inter-American Defense Board from 1964 to 1967. He was recalled to active duty in 1968 to head a board of inquiry into the loss of the nuclear submarine Scorpion.

He had lived in Rockville since retiring from the Navy.

Adm. Austin was born in Wagner, S.C. He graduated from the Naval Academy at Annapolis in 1924. His early career was in submarines. He taught at Annapolis from 1931 to 1934, and was the public relations officer for the Navy Department in Washington from 1937 to 1940.

Among his other decorations were the Distringuished Service Medal, the Legion of Honor and the Bronze Star.

Survivors include his wife, Isabella L. of the home in Rockville; three daughters, Mrs. Nathaniel W. James III, of Vinalhaven, Maine, Mrs. F. T. Watkins Jr., of Alameda, Calif., and Mrs. William Warlick Jr., of Annapolis; his mother, Looula Austin, of Sylvania, Ga.; three sisters Mrs. Edwin Owens, of Sylvania, Mrs. Charles Pratt, of Alexandria, and Mrs. Austin Perry, of Greenville, N.C., and 10 grandchildren.