The unit was deployed to the Southwest Pacific, October–December 1943, and assigned to Fifth Air Force. It was again redesignated as the 312th Bombardment Group (Light) in December 1943. It began operations in New Guinea, flying patrol and escort missions. Following its conversion to the Douglas A-20 Havoc, the group attacked airfields, troop concentrations, gun positions, bridges, and warehouses on the northern and western coasts of New Guinea. It moved to the Philippines in November 1944 and provided support for ground troops and struck airfields and transportation facilities.