John Clerk may refer to:
- John Clerk (fl. 1414), MP for Reading
- John Clerk (fl. 1419–1421), MP for Shaftesbury, perhaps also an attorney or yeoman
- John Clerk (bishop) (died 1541), former bishop of Bath and Wells
- John Clerk of Eldin (1728–1812), Scottish Enlightenment figure, artist, and author of An Essay on Naval Tactics
- John Clerk (writer) (died 1552), English Roman Catholic writer
- John Clerk, Lord Eldin (1757–1832), Scottish judge
- John Clarke (physician, 1582–1653), English physician. His last name was also spelt Clerk.
- John Clerk (physician) (1689–1757), Scottish physician
- Clerk baronets
- John Clerk of Penicuik (1611–1674), Scottish merchant
- Sir John Clerk, 1st Baronet (died 1722), Member of the Parliament of Scotland
- Sir John Clerk, 2nd Baronet (1676–1755), Scottish lawyer, judge, and composer
- Sir John Clerk, 5th Baronet (1736–1798), Royal Navy officer