Harald Gelhaus (24 July 1915 in Göttingen – 2 December 1997 in Bochum) was a German U-boat commander in World War II and recipient of the Knight's Cross of the Iron Cross (German: Ritterkreuz des Eisernen Kreuzes).
The Knight's Cross of the Iron Cross was awarded to recognise extreme battlefield bravery or successful military leadership.
As commander of U-143 and U-107 Harald Gelhaus is credited with the sinking of 19 ships (including SS Clan Alpine) for a total of 100,373 gross register tons (GRT) and further damaging one ship of 10,068 GRT.