Joly is a surname. Notable people with the surname include:
Charles Jasper Joly (1864–1906), Irish mathematician and astronomer
Cyril Bencraft Joly, soldier and writer
Dom Joly (born 1967), British television comedian
Édouard Joly (1898–1982), French aeroplane designer
Eva Joly (born 1943), Norwegian-born French magistrate and politician
Greg Joly (born 1954), Canadian ice hockey player
John Joly (1857–1933), Irish scientist
Maurice Joly (1829-1878), French satirist and lawyer
Rene Joly (born 1965), Canadian-Martian
Sébastien Joly (born 1979), French road-racing cyclist
It is also a given name. Notable people with the given name include:
Joly Braga Santos