Kusaka remained with the fleet until November 1942, and accepted a number of staff positions thereafter. He was promoted to vice admiral on 1 May 1944 and transferred to the Combined Fleet as Chief of Staff under commander-in-chief Admiral Soemu Toyoda in November 1944. His final assignment was command of the 5th Air Fleet after the suicide of Matome Ugaki, exactly the day Japan surrendered to the Allies.