Synnot is a surname. Notable people with the surname include:
- Anthony Synnot KBE, AO (1922–2001), Admiral in the Royal Australian Navy
- Arthur Henry Seton Hart-Synnot (1870–1942), British Army general
- David Synnot (1593–1649), Governor of Wexford during the Sack of Wexford by Cromwell
- Monckton Synnot (1827–1879), prominent squatter in Victoria, Australia
- Sir Walter Synnot (1742–1821), son of Richard Synnot, settled in the parish of Ballymoyer, County Armagh in 1778
- Sir Walter Synnot Manifold (1849–1928), Australian politician
- Timothy Monckton Synnot DSC (1916–1997), officer in the Royal Australian Navy
- Walter Synnot (colonial settler) (fl. 19th century), prominent Australian Colonial, a son of Sir Walter Synnot