SM UB-155[Note 1] was a German Type UB III submarine or U-boat built for the German Imperial Navy (German: Kaiserliche Marine) during World War I.

She was never commissioned into the German Imperial Navy but surrendered to France on 9 March 1919 in accordance with the requirements of the Armistice with Germany and broken up at Brest in July 1921.

UB-155 carried 10 torpedoes and was armed with a 8.8 cm (3.46 in) deck gun.

UB-155 would carry a crew of up to 3 officer and 31 men and had a cruising range of 7,120 nautical miles (13,190 km; 8,190 mi).

Her engines enabled her to travel at 13.5 knots (25.0 km/h; 15.5 mph) when surfaced and 7.5 knots (13.9 km/h; 8.6 mph) when submerged.