SM UB-17 was a German Type UB I submarine or U-boat in the German Imperial Navy (German: Kaiserliche Marine) during World War I. The submarine disappeared during a patrol in March 1918. UB-17 was ordered in November 1914 and was laid down at the AG Weser shipyard in Bremen in February 1915. UB-17 was a little under 28 metres (92 ft) in length and displaced between 127 and 141 tonnes (125 and 139 long tons), depending on whether surfaced or submerged. She carried two torpedoes for her two bow torpedo tubes and was also armed with a deck-mounted machine gun. UB-17 was broken into sections and shipped by rail to Antwerp for reassembly. She was launched in April 1915 and commissioned as SM UB-17 in May.