Douglas R. Ewart (born 13 September 1946 in Kingston, Jamaica) is a Jamaican multi-instrumentalist and instrument builder. He plays sopranino and alto saxophones, clarinets, bassoon, flute, bamboo flutes (shakuhachi, ney, and panpipes), and didgeridoo; as well as Rastafarian hand drums (nyabingi, repeater, and bass).

Ewart emigrated to the United States in June 1963 (coming to Chicago) and became associated with the Association for the Advancement of Creative Musicians (AACM) in 1967, studying with Joseph Jarman and Roscoe Mitchell. He served as that organization's president from 1979 to 1986.

He has performed or recorded with J. D. Parran, Muhal Richard Abrams, Art Ensemble of Chicago, Anthony Braxton, Alvin Curran, Anthony Davis, Robert Dick, Von Freeman, Joseph Jarman, Amina Claudine Myers, Roscoe Mitchell, James Newton, Rufus Reid, Wadada Leo Smith, Cecil Taylor, Richard Teitelbaum, Henry Threadgill, Hamid Drake, Don Byron, Malachi Favors Maghostut, and George Lewis.

In 1992, Ewart collaborated with Canadian artist Stan Douglas on the video installation Hors-champs which was featured at documenta 9 in Kassel, Germany. The installation features Ewart in an improvisation of Albert Ayler's "Spirits Rejoice" with musicians George Lewis, Kent Carter and Oliver Johnson.

He has lived in Minneapolis, Minnesota since 1990. His father, Tom, was a cricket umpire.