USS Frank Knox (DD-742) was a Gearing-class destroyer in the United States Navy during World War II. She was named after Secretary of the Navy Frank Knox. Frank Knox was built at Bath, Maine. Commissioned in December 1944, she arrived in the western Pacific war zone in mid-June 1945, in time to participate in the final carrier air raids on the Japanese home islands as part of Task Force 38. During the Battle of Okinawa she acted as a radar picket destroyer giving early warnings of incoming air raids. She was present in Tokyo Bay when Japan formally surrendered on 2 September 1945 and remained in the Far East until early February 1946. The ship made additional deployments to the region during the later 1940s and was reclassified as a radar picket destroyer (DDR) in March 1949.