Klaus Bargsten (31 October 1911 – 25 October 2000) was the captain and sole survivor of the sunken U-521.

U-521 under Bargsten's command was sunk on 2 June 1943 by the United States submarine chaser PC-565 east of Cape Hatteras.

Bargsten was interrogated and held as a prisoner of war until his release in 1946.

The Kriegsmarine falsely reported the entire crew of U-521 as MIA (Missing in Action).

Bargsten's promotions during World War II.