Otto Kähler (3 March 1894 – 2 November 1967) was a Konteradmiral with the Kriegsmarine during World War II. He commanded the German auxiliary cruiser Thor, a merchant raider, on two combat patrols and sank or captured 12 ships, for a combined tonnage of of Allied shipping. He was also a recipient of the Knight's Cross of the Iron Cross with Oak Leaves (Ritterkreuz des Eisernen Kreuzes mit Eichenlaub). The Knight's Cross of the Iron Cross and its higher grade Oak Leaves was awarded to recognise extreme battlefield bravery or successful military leadership. Kähler relinquished command of Thor on 20 July 1941 to Günther Gumprich, who would also received the Knight's Cross of the Iron Cross as commander of Thor.