German submarine U-717 was a Type VIIC U-boat of Nazi Germany's Kriegsmarine during World War II. The submarine was laid down on 24 April 1942 at the H. C. Stülcken Sohn yard at Hamburg, launched on 20 February 1943, and commissioned on 19 May 1943 under the command of Oberleutnant zur See Siegfried von Rothkirch und Panthen. Attached to 5th U-boat Flotilla based at Kiel, U-717 completed her training period on 31 July 1944 and was assigned to front-line service.
German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-717 had a displacement of 769t when at the surface and 871t while submerged. She had a total length of 67.1m (220.1feet), a pressure hull length of 50.5m (165.7feet), a beam of 6.2m (20.3feet), a height of 9.6m (31.5feet), and a draught of 4.74m (15.55feet). The submarine was powered by two Germaniawerft F46 four-stroke, six-cylinder supercharged diesel engines producing a total of NaNPS for use while surfaced, two Garbe, Lahmeyer & Co. RP 137/c double-acting electric motors producing a total of 750PS for use while submerged. She had two shafts and two 1.23abbr=onNaNabbr=on propellers. The boat was capable of operating at depths of up to .
The submarine had a maximum surface speed of and a maximum submerged speed of . When submerged, the boat could operate for at ; when surfaced, she could travel at . U-717 was fitted with five 53.30NaN0 torpedo tubes (four fitted at the bow and one at the stern), fourteen torpedoes, one 8.82NaN2 SK C/35 naval gun, 220 rounds, and two twin 2sp=usNaNsp=us C/30 anti-aircraft guns. The boat had a complement of between forty-four and sixty.
In the last days of World War II, U-717 was scuttled with other U-boats during Operation Regenbogen in Flensburg Firth on 5 May 1945 in position 54.8167°N 36°W.