Ken Vandermark (born September 22, 1964) is an American jazz composer, saxophonist, and clarinetist.

A fixture on the Chicago-area music scene since the 1990s, Vandermark has earned wide critical praise for his playing and his multilayered compositions, which typically balance intricate orchestration with passionate improvisation. He has led or been a member of many groups, has collaborated with many other musicians, and was awarded a 1999 MacArthur Fellowship. He plays tenor saxophone, clarinet, bass clarinet, and baritone saxophone.

He was also a member of NRG Ensemble.