Klaus Wennemann (18 December 1940 – 7 January 2000) was a German actor. He was best known for his roles as the Chief Engineer (the LI) in Das Boot and as Faber in the TV series Der Fahnder. He died at the age of 59 from lung cancer.
Wennemann was good friends with Jürgen Prochnow. Their real-life friendship helped the on-screen friendship between their characters in Das Boot.