During his postwar years, O'Donnell commanded Destroyer Division 32 and served on the staffs of the Bureau of Ordnance and Commander of Naval Forces in Germany. He then commanded the USS "George Clymer" in operations off Korea and Japan in 1952 and 1953. O'Donnell next served as commander of the USS "New Jersey" and was sworn in on March 18, 1955. He also commanded Destroyer Flotilla 6 from June 1956 to October 1957.