German submarine U-317 was a Type VIIC/41 U-boat of Nazi Germany's Kriegsmarine during World War II.
The submarine was laid down on 12 September 1942 at the Flender Werke at Lübeck, launched on 1 September 1943, and commissioned on 23 October 1943 under the command of Oberleutnant zur See Peter Rahlf.
German Type VIIC/41 submarines were preceded by the heavier Type VIIC submarines. U-317 had a displacement of 759t when at the surface and 860t 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-317 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), one 3.7cm (01.5inches) Flak M42 and two 2sp=usNaNsp=us C/30 anti-aircraft guns. The boat had a complement of between forty-four and sixty.
U-317 served with the 4th U-boat Flotilla for training, and later with the 9th U-boat Flotilla in front-line service from 1 to 26 June 1944.
U-317s first patrol took her from Kiel in Germany to Egersund in Norway, between 31 May and 2 June 1944. She then sailed from Egersund on 21 June for her second and final patrol.
U-317 was sunk with all hands on 26 June 1944, northeast of the Shetland islands, in position 62.05°N 46°W, by depth charges dropped by a Liberator anti-submarine bomber of No. 86 Squadron RAF.