John Fenwick may refer to:
John Fenwick (14th century MP) for Northumberland (UK Parliament constituency) Sir John Fenwick, 1st Baronet (c. 1570–1658), English landowner John Fenwick (MP for Morpeth) (d. 1644), English politician and soldier who was killed at the Battle of Marston Moor John Fenwick (Quaker) (1618–1683), English founder of a Quaker colony in Salem, New Jersey John Fenwick (Jesuit) (c. 1628–1679), English Jesuit Sir John Fenwick, 3rd Baronet (c. 1645–1697), English Jacobite conspirator John Ralph Fenwick (1761–1855), English physician and radical John Fenwick Burgoyne Blackett (c. 1821–1856), British politician John Fenwick (bishop), Free Church of England bishop
Also John Fenwicke (c. 1593–1670), supported the parliamentary cause during the English Civil War. John Fenwick Service Area, a service area for travelers using the New Jersey Turnpike