Bagenal or Bagnal is a surname, and may refer to:
Nicholas Bagenal (c. 1509–1591), English-born Marshal of the Irish Army Dudley Bagenal (1554–1587), soldier in Ireland, son of Nicholas Henry Bagenal (c. 1556–1598), Marshal of the Irish Army, son of Nicholas Mabel Bagenal (c. 1571–1595), Anglo-Irish noblewoman, daughter of Nicholas Dudley Bagenal (Jacobite) (1638–1712), Jacobite politician Lord Walter Bagenal (1670–1745), founder of Bagenalstown, son of the above Beauchamp Bagenal (1741–1802), Irish politician, son of the above Walter Bagenal (1762–1814), Irish politician Hope Bagenal (1888–1979), British architectural theorist Fran Bagenal (born 1954), professor at University of Colorado Boulder
See also Bagnall (disambiguation)