German submarine U-624 was a Type VIIC U-boat built for Nazi Germany's Kriegsmarine for service during World War II. She was laid down on 15 July 1941 by Blohm & Voss in Hamburg as yard number 600, launched on 31 March 1942 and commissioned on 28 May 1942 under Kapitänleutnant Ulrich Graf von Soden-Fraunhofen.
German Type VIIC submarines were preceded by the shorter Type VIIB submarines. U-624 had a displacement of when at the surface and while submerged. She had a total length of , a pressure hull length of , a beam of , a height of , and a draught of . The submarine was powered by two Germaniawerft F46 four-stroke, six-cylinder supercharged diesel engines producing a total of for use while surfaced, two Brown, Boveri & Cie GG UB 720/8 double-acting electric motors producing a total of for use while submerged. She had two shafts and two 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-624 was fitted with five torpedo tubes (four fitted at the bow and one at the stern), fourteen torpedoes, one SK C/35 naval gun, 220 rounds, and a C/30 anti-aircraft gun. The boat had a complement of between forty-four and sixty.
The boat's service began on 28 May 1942 with training as part of the 8th U-boat Flotilla. She was transferred to the 7th Flotilla, operating out of St.Nazaire, on 1 October 1942 for active service in the North Atlantic .
In just two patrols she sank five merchant ships and three warships for a total of and 873 tons, plus one merchant ship damaged.
U-624 was sunk on 7 February 1943 in the North Atlantic in position . She was caught unawares on the surface whilst transmitting to base a lengthy report of the previous night's action around Convoy SC 118. A RAF B-17 Flying Fortress aircraft of (Sqdn. 220/J), operating out of Londonderry Port, depth charged her astern of the convoy. All 45 hands were lost.
U-624 took part in five wolfpacks, namely: