Type U 13 was a class of three gasoline powered U-boats used during World War I by the Imperial German Navy. The boats were built between 1909 and 1911 and commissioned into the Navy during 1912. Each of the three boats was lost during the first year of the war.
Type U 13s had an overall length of The boats' beam was , the draught was . The boats displaced when surfaced and when submerged.
Type U 13s were fitted with two Körting 6-cylinder and two 8-cylinder two-stroke paraffin engines with a total of for use on the surface and two SSW double-acting electric motors with a total of for underwater use. These engines powered two shafts, which gave the boats a top surface speed of , and when submerged. Cruising range was at on the surface and at submerged. Constructional diving depth was .
The U-boats were armed with four torpedo tubes, two fitted in the bow and two in the stern, and carried six torpedoes. The boats' complement was 4 officers and 25 enlisted.
All three Type U 13 boats were built at Kaiserliche Werft Danzig between 1909 and 1911.