HNLMS K XI was the first of three K XI-class submarines of the Royal Netherlands Navy, built to serve as a patrol vessel in the Dutch colonies.

Before departing for the Dutch East Indies she sailed on an exhibition tour to the Baltic Sea along with the submarine O 8, the pantserschip Marten Harpertzoon Tromp and Jacob Van Heemskerck, and the torpedo boats Z3 and Z5.

In early 1941 K XI was part of the 2nd Division of the Dutch East Indies Submarine Flotilla, with K X, K XII and K XIII.

From 8 December 1941 to 23 January 1942, K XI fell under British operational command and conducted patrols east of Malaya.

The submarine was salvaged six weeks later, K XI was stripped further before being towed out to the "Ships Graveyard" site west of Rottnest Island and scuttled in September 1946.