Bailly may refer to:
- Jean Sylvain Bailly (1736-1793), French astronomer and orator, one of the leaders of the early part of the French Revolution
- Joseph Bailly (1774-1835), French-Canadian fur trader and pioneer
- Logan Bailly (born 1985), Belgian football goalkeeper
- Mother Mary Cecilia Bailly (1815-1898), American nun and general superior of the Sisters of Providence of Saint Mary-of-the-Woods, Indiana
- Sandrine Bailly (born 1979), French biathlete
- Bailly (crater), a lunar crater
Bailly is the name or part of the name of several communes in France:
- Bailly, Oise
- Bailly, Yvelines
- Bailly-aux-Forges, in the Haute-Marne département
- Bailly-en-Rivière, in the Seine-Maritime département
- Bailly-le-Franc, in the Aube département
- Bailly-Romainvilliers, in the Seine-et-Marne département