SM U-106 was one of the 329 submarines serving in the Imperial German Navy in World War I. U-106 was commissioned on 28 July 1917, under the command of Kapitänleutnant Hans Hufnagel, and participated in one wartime patrol starting on 2 September 1917.

On 18 September 1917, during the First Battle of the Atlantic, U-106 was credited with the sinking of HMS Contest, an Acasta class destroyer, and damaging "City of Lincoln", a 5,867 GRT steamer, in the Western Approaches.

[1] When submerged, she could operate for 50 nautical miles (93 km; 58 mi) at 5 knots (9.3 km/h; 5.8 mph); when surfaced, she could travel 9,280 nautical miles (17,190 km; 10,680 mi) at 8 knots (15 km/h; 9.2 mph).

[1] In 2009 the Royal Netherlands Navy found the wreckage of the ship north of Terschelling, while charting sea-routes.

The news was made public in March 2011, after the ship's identity had been confirmed by German authorities and the crewmembers' families had been informed.