Following a cruise to Europe during the summer of 1919, Bernadou joined Division 19, Atlantic Fleet, and cruised along the east coast until placed out of commission at Philadelphia Navy Yard 1 July 1922. She Joined Squadron 7, Scouting Force, after recommissioning 1 May 1930. Out of service September 1936–October 1939, she then rejoined the fleet for service with Destroyer Division 6, Atlantic Squadron, on Neutrality Patrol.
She helped convoy the Marines to Iceland (1–7 July 1941) and, except for one crossing to Britain, remained on the Newfoundland-Iceland convoy run until the fall of 1942. On 25 October 1942 she departed Norfolk, Va., to take part in the Invasion of North Africa (8–11 November). She was awarded the Presidential Unit Citation for landing assault troops inside the harbor of Safi, French Morocco.
Returning to Boston 26 November she remained on east coast convoy duty until February 1943. Bernadou made a convoy run to Gibraltar during March and April and on 10 May departed Norfolk for Oran, Algeria. She operated from Oran until December 1943, during which time she took part in the occupation of Sicily (9–12 July); Salerno landings (9–10 and 21–23 September); and escorted Mediterranean convoys.
She returned to the United States in December 1943 and escorted two convoys to North Africa (22 February–9 June 1944) before retiring to the less rigorous East Coast–Caribbean runs. From October 1944 to May 1945 she served as plane guard and escort vessel during carrier exercises off the East Coast. She arrived at Philadelphia Navy Yard 8 June 1945; was decommissioned 17 July; and sold 30 November 1945.
In addition to her Presidential Unit Citation, Bernadou received five service stars for operations in World War II.