Theodore Marier, American composer and educator, founded the Boston Archdiocesan Choir School (d. 2001)

Theodore Norbert Marier (October 17, 1912 – February 24, 2001) was a church musician, educator, arranger and scholar of Gregorian Chant. He founded St. Paul's Choir School in Cambridge, Massachusetts in 1963, and served as the second president of the Church Music Association of America.