James Arnold may refer to:
- James Arnold (1781–1868), whaling merchant and benefactor of the Arnold Arboretum in Boston, Massachusetts
- James Arnold (author & artist) (1909–1999), English author and artist
- James Arnold (Australian politician) (1902–1967), Australian Senator
- James Arnold (cricketer) (1869–1944), English cricketer
- James Arnold (New Zealand politician) (1859–1929), New Zealand politician and trade unionist
- James Edward Arnold (1939–2007), California businessman
- James Henry Arnold (1759–1836), British lawyer, Admiralty Advocate and fellow of the Royal Society
- James M. Arnold (1838–1897), associate justice and chief justice of the Supreme Court of Mississippi
- James Newell Arnold (1844–1927), collector and publisher of genealogical and historical records of the state of Rhode Island
- James R. Arnold (1923–2012), planetary scientist and chemist