The "Die Hard" star showed off his musical talents at the Jazz Foundation of America's annual show, held at New York's Apollo Theater, in honour of Dr John and McCoy Tyner, reported Contactmusic.
Willis served as back up on the harmonica for blues veteran Henry Gray as he played the piano, while the Hollywood action man later took over the microphone to sing the blues with a cover of Roomful of Blues' "She'll Be So Fine."
Ringo Starr also made an appearance via a pre-recorded video to introduce Dr John's performance, which featured the former Beatles' star's first All-Starr band.