SM UB-133[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.

Completed after the end of hostilities, she was not commissioned into the German Imperial Navy but surrendered to Britain in accordance with the requirements of the Armistice with Germany.

[2] She was built by Friedrich Krupp Germaniawerft of Kiel and following just under a year of construction, launched at Kiel on 27 September 1918.

UB-133 carried 10 torpedoes and was armed with a 10.5 cm (4.13 in) deck gun.

UB-133 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).