HMS Prefect (Z263) was a net laying ship for the Royal Navy during the Second World War acquired from the United States Navy in June 1944 via Lend-Lease. The ship was laid down as Prefect (YN-88), a net tender of the Ailanthus class, on 1 April 1943 at the American Car and Foundry Co. in Wilmington, Delaware. On 17 January 1944, while still under construction, the ship was reclassified as a net laying ship and redesignated AN-75. Prefect was launched on 8 March and completed on 3 June.