St. George was laid down on 4 August 1943 by the Seattle-Tacoma Shipbuilding Corporation, Tacoma, Washington, launched on 14 February 1944, sponsored by Mrs. Alfred E. Montgomery; and commissioned on 24 July 1944.

Thanks to a warning from Louis (Jack) Norvelle Tickle, an airplane mechanic who had been on deck at the time and was able to spot the Japanese before they hit, only three men were killed.

She left Kerama Retto on 12 July for drydocking and repairs at Guam, returning on 21 August to Okinawa, where she rode out a typhoon on 16 and 17 September.

On 20 September, the seaplane tender sailed to Wakayama Wan, Japan, where her aircraft provided surveillance of the Japanese Inland Sea and supplied passenger, mail, and courier service between Tokyo, Sasebo, and Okinawa.

USS St. George was struck from the Navy list on 1 July 1963 and simultaneously transferred to the Maritime Administration's reserve fleet at Suisun Bay, California.