The Frederick Harris Music Co., Limited (Frederick Harris Music) is a music publishing firm in Toronto, Ontario, Canada, founded in 1904. The company claims to be the oldest music publishing company in Canada, and has supported the work of composers including Boris Berlin, Sir Ernest MacMillan, and Healey Willan. In addition to repertoire for piano, guitar, violin, flute and voice, the Frederick Harris Music catalogue also includes publications for ear training, sight reading, technique, theory, harmony, and music history.