SM UB-122 was a German Type UB III submarine or U-boat in the German Imperial Navy (German: Kaiserliche Marine) during World War I. She was commissioned into the German Imperial Navy on 4 March 1918 as SM UB-122. UB-122 was surrendered to the Allies at Harwich on 20 November 1918 in accordance with the requirements of the Armistice with Germany. Having been exhibited at Southampton in December 1918, she was then laid up at Portsmouth until scuttled in the English Channel on 1 July 1921.