German submarine U-266 was a Type VIIC U-boat of Nazi Germany's Kriegsmarine during World War II. The submarine was laid down on 1 August 1941 at Bremer-Vulkan-Vegesacker Werft in Bremen as yard number 31. She was launched on 11 May 1942 and commissioned on 24 June under the command of Oberleutnant zur See Hannes Leinemann. In two patrols, she sank four ships of 16,089 gross register tons (GRT). She was a member of five wolfpacks. She was sunk on 15 May 1943 in mid-Atlantic by a British aircraft.