26th U-boat Flotilla ("26. Unterseebootsflottille") was a training flotilla ("Ausbildungsflottille ") of Nazi Germany's Kriegsmarine during World War II. The flotilla was formed at Pillau in April 1941 under the command of Korvettenkapitän Hans-Gerrit von Stockhausen. The flotilla trained newly commissioned U-boats in the firing of torpedoes (Torpedoschiessausbildung), a course which lasted for three to four weeks. In 1945, as the Russians advanced deeper into Eastern Europe, the flotilla relocated to Warnemünde. The flotilla was disbanded in May 1945 when Germany surrendered.