USS Jefferson County (LST-845) was an LST-542-class tank landing ship built for the United States Navy during World War II. Named after counties in 25 states, she was the only U.S. Naval vessel to bear the name. USS LST-845 was laid down by the American Bridge Company, Ambridge, Pennsylvania, on 23 October 1944; launched on 7 December 1944; sponsored by Mrs. B. F. Fairless; and commissioned at New Orleans, Louisiana, on 1 January 1945 with Lieutenant C. E. Lowe in command.