Mitch Leigh was an American musical theatre composer and theatrical producer best known for the musical Man of La Mancha.

Man of La Mancha is a 1965 musical with a book by Dale Wasserman, music by Mitch Leigh, and lyrics by Joe Darion. It is adapted from Wasserman's non-musical 1959 teleplay I, Don Quixote, which was in turn inspired by Miguel de Cervantes and his 17th-century novel Don Quixote. It tells the story of the "mad" knight Don Quixote as a play within a play, performed by Cervantes and his fellow prisoners as he awaits a hearing with the Spanish Inquisition. The work is not and does not pretend to be a faithful rendition of either Cervantes' life or Don Quixote. Wasserman complained repeatedly about people taking the work as a musical version of Don Quixote.