German submarine U-703 was a Type VIIC U-boat of the German Kriegsmarine deployed during the Second World War against allied shipping in the Arctic Ocean. She was a successful boat, which had a far longer service life than most other U-boats, primarily due to the restricted zone of operations in which she fought. Her main mission during the war was to target the Arctic Convoys which carried supplies to the Soviet Union from Britain. At this she was quite successful in her three years of raiding until her presumed demise in 1944.