Rosier is the surname of a wizarding family and can refer to:
- Vinda Rosier, a woman who lived during the 1920s
- Rosier (male), one of the earliest Death Eaters
- Evan Rosier, a later Death Eater and contemporary of the Marauders
- Druella Rosier, wife of Cygnus Black III and mother of Bellatrix, Andromeda, and Narcissa Black