With elements of the 1st Marine Provisional Brigade embarked, "Gunston Hall" departed San Diego 1 July 1950 and reached Pusan, Korea, via Yokosuka 3 August. Disembarking the Marines, she took aboard 30 stretcher cases and returned to Osaka, Japan. On 10 September "Gunston Hall" sailed from Japan to participate in the amphibious operation at Inchon, Korea, 15 September. After the Marines had landed midway up the peninsula, threatening to cut the communist supply lines to their troops at the tip of the peninsula, "Gunston Hall" made several shuttle trips to bring reinforcements. As the Korean War settled into its long and bloody pattern of near stalemate, "Gunston Hall" continued to shuttle troops and supplies between Japan and Korea. During an overhaul in the summer of 1952, she was fitted with a helicopter landing and launching platform large enough to accommodate nine "whirly-birds", the newest element in amphibious warfare.