Karel Ančerl (11 April 1908 – 3 July 1973) was a Czechoslovak conductor and composer, renowned especially for his performances of contemporary music and for his interpretations of music by Czech composers.

Ančerl was born into a prosperous Jewish family in the village of Tučapy in southern Bohemia. After graduating from the Prague Conservatory, he pursued his conducting studies under Hermann Scherchen and Václav Talich. He was the assistant conductor at the Munich premiere of Alois Hába's quarter-tone opera Mother (1931) and conducted the orchestra of the avant-garde theatre Osvobozené divadlo in Prague (1931–1933). Conducting work for Czechoslovak radio was interrupted by World War II which resulted in his being imprisoned with his family in the Theresienstadt concentration camp in 1942 and then sent to Auschwitz in 1944. Unlike his wife and young son, Ančerl survived Auschwitz.

After the war, Ančerl conducted for Radio Prague until 1950, when he became artistic director of the Czech Philharmonic, a post he held successfully for eighteen years. Following the 1968 invasion of Czechoslovakia, Ančerl emigrated to Toronto, Canada, where he worked as music director of the Toronto Symphony Orchestra until his death in 1973.

As a conductor, Ančerl helped foster a distinctly Czech orchestral sound, both within the Czech Philharmonic and elsewhere. Highly regarded also as a studio artist, Ančerl made a wide range of recordings on the Supraphon label, including repertoire by various Czech composers (remastered in the Karel Ančerl Gold Edition).