SM UB-71 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 23 November 1917 as SM UB-71.^{[Note 1]}

UB-71 was serving in the Mediterranean when she was sunk by depth charges from HMS ML413 off Menorca on 21 April 1918.^[2]

She was built by Friedrich Krupp Germaniawerft of Kiel and following just under a year of construction, launched at Kiel on 12 July 1917. UB-71 was commissioned later that same year under the command of Kptlt. Kurt Schapler. Like all Type UB III submarines, UB-71 carried 10 torpedoes and was armed with a 8.8 cm (3.46 in) deck gun. UB-71 would carry a crew of up to 3 officer and 31 men and had a cruising range of 9,090 nautical miles (16,830 km; 10,460 mi). UB-71 had a displacement of 513 t (505 long tons) while surfaced and 647 t (637 long tons) when submerged. Her engines enabled her to travel at 13.2 knots (24.4 km/h; 15.2 mph) when surfaced and 7.6 knots (14.1 km/h; 8.7 mph) when submerged.