After extensive training on both coasts, Frank Knox arrived in San Pedro Bay, P.I., on 16 June 1945 to join the fast carrier task forces in their raids against the Japanese home islands. With such a force, she entered Sagami Wan on 27 August, and was present in Tokyo Bay during the surrender ceremonies on 2 September. She served on occupation duty in the Far East until sailing for San Diego, her home port, on 4 January 1946.

In 1947 and 1948, Frank Knox completed tours of duty in the Far East, and upon the outbreak of the Korean War, sailed on 6 July 1950 to join the Seventh Fleet’s fast carrier task force in air operations against North Korea. During her tour of duty, she also took part in the Inchon invasion, conducted shore bombardments, patrolled the Taiwan Straits and, on 30 January 1951, joined in a mock invasion of the North Korean coast. This deception proved so effective that Communist troops were withdrawn from central Korea for a time. A final 40-day period was spent in bombardment of the east coast rail centers, Chongjin and Songjin, cutting supply and communications routes.

Returning to San Diego 11 April 1951, Frank Knox operated along the west coast and in the Hawaiians until 19 April 1952, when she sailed for Korean service again. Her duty, similar to that of her first wartime tour, included several weeks in Wonsan Harbor to give fire support to minesweepers. The destroyer returned to West Coast duty on 18 November 1952. During her 1953 Far Eastern cruise, which coincided with the Korean armistice, Frank Knox conducted patrols, and covered the transportation of former Chinese prisoners of war who had elected to go to Taiwan rather than return from Korea to mainland Communist China.

Her next tour of duty in the western Pacific, in 1955, found Frank Knox taking part in the evacuation of the Tachen Islands. Her annual deployments to the Far East through 1962 included intensive training operations, often with ships of foreign navies, and good will visits to many ports under the President’s “People-to-People” program. Several times she visited ports in Australia and New Zealand.

Frank Knox received one battle star for World War II service and five for Korean War service.