John Merrill Knapp (May 9, 1914 – March 7, 1993) was an American musicologist and academic.
Born in New York City, Knapp graduated from the Hotchkiss School before entering Yale University where he earned a Bachelor of Arts in 1936 and was a member of Skull and Bones.
He left there to pursue graduate studies at Columbia University where he earned a Master of Music degree.
He served as an operations officer in the Third Fleet of United States Navy during World War II (1942-1946); earning two service stars and a commendation ribbon.
He was chairman of Princeton's music department from 1949-1951, and served as Dean of the whole college from 1961-1966.