SM UC-26 was a German Type UC II minelaying submarine or U-boat in the German Imperial Navy (German: Kaiserliche Marine) during World War I. The U-boat was ordered on 29 August 1915 and was launched on 22 June 1916. She was commissioned into the German Imperial Navy on 18 July 1916 as SM UC-26. In nine patrols UC-26 was credited with sinking 39 ships, either by torpedo or by mines laid. UC-26 was rammed and sunk by HMS Milne off Calais on 8 May 1917.