Dimitri Mitropoulos (Greek: Δημήτρης Μητρόπουλος; 1 March [O.S. 18 February] 1896 – 2 November 1960), was a Greek conductor, pianist, and composer. He received international fame both as a major conductor and composer of the 20th century.

Mitropoulos was noted as a champion of modern music, such as that by the members of the Second Viennese School. He wrote a number of pieces for orchestra and solo works for piano, and also arranged some of Johann Sebastian Bach's organ works for orchestra. In addition he was very influential in encouraging Leonard Bernstein's interest in conducting performances of Mahler's symphonic works. He also premiered and recorded a piano concerto of Ernst Krenek as soloist (available on CD), and works by composers in the U.S. such as Roger Sessions, Elie Siegmeister and Peter Mennin. In 1952 he commissioned American composer Philip Bezanson to write a piano concerto, which he premiered the following year. His compositions include a piano sonata and the opera Sœur Béatrice (1918).