Following shakedown and antisubmarine exercises, "Maddox" departed Boston on 27 August for Norfolk, Virginia on route to the Pacific. Arriving at Ulithi 21 October 1944, she was assigned to Fast Carrier TG 38.1 of the 3d Fleet. As a member of this task group, "Maddox" took part in the preparation and the covering operations for the Mindoro and Luzon invasions, 4 November 1944 to 21 January 1945. During this period she served in the screen and on picket station in the South and East China Seas, while carrier-based planes struck air and naval bases from Saigon to Formosa. Hit by a "kamikaze" off Formosa on 21 January 1945, "Maddox" headed for Ulithi for repairs. Departing on 14 March, the destroyer steamed off the Japanese home islands where she was on picket station during the air strikes on Kyushu and southern Honshu. She proceeded to Okinawa on 23 March to provide support for preinvasion strikes, remaining on duty there after the invasion date of 1 April. For almost three months, until 13 June 1945, "Maddox" continued to provide support for this campaign in the form of shore bombardment and carrier screening for raids on Kyushu and Shikoku.