Jermyn is a surname, and may refer to:
Ambrose Jermyn (1511–1577), English courtier, magistrate and landowner George Bitton Jermyn (1789–1857), English cleric and antiquarian Henry Jermyn, 1st Earl of St Albans (c.1604–1684) Henry Jermyn, 1st Baron Dover (c.1636–1708) Henry Jermyn (antiquary) (1767–1820), English antiquarian Hugh Jermyn (1820-1903), Anglican bishop James Jermyn, Anglican priest in New Zealand John Jermyn (field hockey) (born 1982), Irish field hockey player John Wesley Jermyn, homeless street performer in Los Angeles Laetitia Jermyn (1788–1848), British entomologist, illustrator and author Mark Jermyn (born 1981), British footballer Robert Jermyn (1539–1614), English landowner and politician Robert Jermyn (1601–1623), English Member of Parliament, grandson of Robert Jermyn (1539–1614) Sir Thomas Jermyn (died 1552), English knight Thomas Jermyn (1561–1607), Member of Parliament Thomas Jermyn (1573–1645), English Royalist soldier and politician Thomas Jermyn (1604–1659). English courtier and politician Thomas Jermyn, 2nd Baron Jermyn (died 1703), English Member of Parliament, nephew of Henry Jermyn, 1st Baron Dover