Asmus Nicolai Clausen (2 June 1911 – 16 May 1943) was a German U-boat commander of the Second World War. He is credited with sinking 23 ships for a total of of Allied shipping. He was also a recipient of the Knight's Cross of the Iron Cross (). The Knight's Cross of the Iron Cross was awarded to recognise extreme battlefield bravery or successful military leadership. Clausen and U-182 were lost with all hands, sunk on 16 May 1943 by the American destroyers USS MacKenzie and USS Lamb.