Samuel Arnold (10 August 1740 – 22 October 1802) was an English composer and organist.

Arnold was born in London (his mother is said to have been Princess Amelia; his father was Thomas Arnold). He began writing music for the theatre in about the year 1764. A few years later, he became the director of music at Marylebone Gardens, for which he wrote much of his popular music. In 1777, he worked for George Colman the Elder at the Little Theatre, Haymarket. In 1783, he became organist at the Chapel Royal and in 1793 he became the organist at Westminster Abbey, where he was eventually buried. He also wrote the earliest version of Humpty Dumpty. He was a close friend and associate of Haydn.