Karel Ancerl (April 11, 1908 - July 3, 1973) was a Czech conductor.

He studied under Hermann Scherchen and later worked with Vaclav Talich among others. From 1933 to 1939 and again from 1947 to 1950 he conducted for Prague radio. From 1950 to 1968 he was conductor of the Czech Philharmonic Orchestra, and from 1969 to his death conducted the Toronto Symphony Orchestra. He died in Toronto. He was particularly noted for his interpretation of music by Czech composers.