Phoebe Palmer Knapp (March 9, 1839 – July 10, 1908) was an American composer of music for hymns and an organist.
Knapp was born in New York City. Her parents were Walter C. Palmer and Phoebe Worrall Palmer. She married Joseph Fairchild Knapp, one of the founders and the second president of the Metropolitan Life Insurance Company. He had a pipe organ installed in their apartment.She and her husband were members of the John Street Methodist Episcopal Church in New York City. The hymn writer Fanny Crosby was also a member of that church and a friend of Palmer's.