H.M.S. Pretoria Castle
- Class: PretoriaCastle - 1 escort carrier of 1943
- Displacement: 10,231 tons
- Dimensions: 467'3" (oa) x 56' x 21'7"
- Machinery: Burmeister & Wain diesels, twin screw, bhp = 18.5 knots
- Armament: 4-4in AA (2x2), 8-2pdr AA (2x4), 20-20mm AA (10x2) guns
- Aircraft: 6
- Complement: 480
- Builder: Harland & Wolff, Limited, Belfast, Northern Ireland
- Launched: 12 Oct 1938
- Completeed: 18 Apr 1939
- Commissioned: 28 Nov 1939
- Service: Built as a passenger liner for the Union Castle Line with capacity for 555 passengers (220 first class, 335 tourist class). London-around Africa service. Taken over as armed merchant cruiser, armed with 8-6in and 2-12pdr AA, 1939-42. Bought outright in Jul 1942 and sent for conversion to an escort carrier at the Swan Hunter shipyard in Tyne and Wear. She was the largest escort carrier operated by the Royal Navy. Starting in Jul 1943 she operated mainly as a trials and training carrier, making only one operational voyage escorting a convoy to Iceland and another convoy on the return.
Reconverted to passenger ship 1946-47; renamed Warwick Castle. Resumed African sailings, 1947-62. Scrapped in Spain, 1962.