St John Zachary (meaning "St John son of St Zachary", i.e. John the Baptist) was a church, first mentioned in official records in 1181, within the City of London, England, on the north side of Gresham Street, Aldersgate. Its vicar from 25 May 1424 to an unknown date was William Byngham, the founder of England's first teacher training college It was destroyed in the Great Fire of London in 1666 and not rebuilt, with its parish being reunited with that of St Anne and St Agnes by Act of Parliament in 1670- an arrangement that lasted until the 20th century. Its site is now a garden first made by the fire watchers in 1941. Partial records survive at IGI.