HMS LST-421 was a United States Navy LST-1-class tank landing ship that was transferred to the Royal Navy during World War II.

LST-421 was laid down on 11 November 1942, under Maritime Commission (MARCOM) contract, MC hull 941, by the Bethlehem-Fairfield Shipyard, Baltimore, Maryland; launched 5 December 1942; then transferred to the United Kingdom and commissioned on 26 January 1943.

[3] LST-421, in company with sister ships LST-324 and LST-412, left New York, 13 March 1943, with refinery equipment bound for Curaçao, she then sailed to Freetown, Sierra Leone.

She was decommissioned and returned to United States Navy custody on 29 November 1946, and struck from the Naval Vessel Register on 1 August 1947.

The tank landing ship was sold to the Tung Hwa Trading Co., Singapore, on 7 October 1947 and converted for merchant service.