German submarine U-300 was a Type VIIC/41 U-boat of the Nazi German Kriegsmarine during World War II. The submarine was laid down on 9 April 1943 by the Bremer Vulkan yard at Bremen-Vegesack as 'werk' 65. She was launched on 23 November 1943, and commissioned on 29 December 1943 under the command of Oberleutnant zur See Fritz Hein. U-300 served with the 8th U-boat Flotilla for training, the 7th U-boat Flotilla from 1 August 1944 to 30 September 1944 and the 11th U-boat Flotilla from 1 October 1944 to 22 February 1945 for operations. She carried out three patrols, sinking two ships, and damaged two more before she was sunk on 22 February 1945 off Cadiz, Spain.