John Comyn may refer to:
John Comyn (bishop) (1150–1212), Archbishop of Dublin John Comyn (died 1242), styled Earl of Angus John Comyn I of Badenoch (died c. 1275) John Comyn II of Badenoch (died 1302), son of John I, Guardian of Scotland John Comyn III of Badenoch (died 1306), killed by Robert the Bruce John Comyn IV of Badenoch (c. 1294–1314), son of John III John Comyn, Earl of Buchan (died 1308), cousin of John III John Comyn of Ulceby (died c. 1332), Anglo-Scottish noble
See also John Comyns (1667–1740), English judge and MP John Cornyn (born 1952), American politician