In August 1943, the squadron moved to the new field at Munda in the Central Solomon Islands and flew their first mission from there on August 14, 1943. Their arrival on Munda coincided with the landings on Vella Lavella which were constantly under attack from Japanese aircraft based on Bougainville. VMF-123 was one of many squadrons that fought Japanese aircraft for control of the skies over Vella Lavella. The squadron was split up in September 1943 with half remaining on Munda and the other half moving to a field in the Russell Islands. Their last mission in the South Pacific was flown in November 1943 and the squadron returned to the United States on December 14, 1943.