German submarine U-1166 was a Type VIIC/41 U-boat of Nazi Germany's Kriegsmarine during World War II. She was ordered on 14 October 1941, and was laid down on 4 February 1943, at Danziger Werft AG, Danzig, as yard number 138. She was launched on 28 August 1943, and commissioned under the command of Oberleutnant zur See Herbert Wagner on 8 December 1943.