Samuel Arnold may refer to:

• Samuel Arnold (composer) (1740–1802), English composer and organist
• Samuel Arnold (Connecticut politician) (1806–1869), U.S. Representative from Connecticut
• Samuel Arnold (conspirator) (1834–1906), co-conspirator of a plot to kidnap U.S. President Abraham Lincoln
• Samuel G. Arnold (1821–1880), U.S. Senator from Rhode Island
• Samuel James Arnold (1774–1852), English dramatist
• Samuel W. Arnold (1879–1961), U.S. Representative from Missouri
• Samuel Arnold (actor) (born 1992), French actor