German submarine U-677

German submarine U-677 was a Type VIIC U-boat of Nazi Germany's Kriegsmarine during World War II. The submarine was laid down on 13 June 1942 at the Howaldtswerke yard at Hamburg, launched on 6 July 1943, and commissioned on 20 September 1943 under the command of Oberleutnant zur See Paul Weber.

Attached to 5th U-boat Flotilla based at Kiel, U-677 completed her training period on 31 May 1944 and was assigned to front-line service.

Service history
During a British air raid on Hamburg on 5 April 1945, U-677 was damaged while in the Howaldtswerke yard. In a second air raid four days later, U-677 as well as an other U-boat, GS U-982, sank in the U-boat pen Fink II.