Regnier
Régnier or Regnier is a French given name, personal name and surname, and may refer to:
Surname
Personal name
- Regnier I, Count of Hainaut (850–915), son of Gislebert, Count of Darnau and Ermengarde of Lorraine
- Regnier II, Count of Hainault (born 890), son of Regnier I, Count of Hainaut and Hersent of France
- Regnier III, Count of Hainaut (circa 920–973), son of Regnier II, Count of Hainaut
- Regnier de Graaf (1641–1673), Dutch physician and anatomist
- Rainerius, patron saint of Pisa
Other
- Régnier Motor Company, an aircraft engine manufacturer founded by Émile Régnier