Castel is a surname. Notable people with the surname include:
Charles-Irénée Castel de Saint-Pierre (1658–1743), French writer Jean-Gabriel Castel (1928–2023), Canadian law professor Louis Bertrand Castel (1688–1757), French mathematician Moshe Castel (1909–1991), Israeli artist P. Kevin Castel (born 1950), U.S. District Judge, Southern District of New York René Richard Louis Castel (1758–1832), French poet and naturalist Robert Castel (1933–2013), French sociologist
See also Castel (disambiguation) Castle (surname) Castillo (surname)