German submarine U-734 was a Type VIIC U-boat built for Nazi Germany's Kriegsmarine for service during World War II. She was laid down on 20 October 1941 by Schichau-Werke, Danzig as yard number 1525, launched on 19 September 1942 and commissioned on 5 December 1942 under Oberleutnant zur See Hans-Jörg Blauert.