Dalmau is a surname and may refer to:
- Albert Dalmau (born 1992), Spanish footballer
- Christian Dalmau (born 1975), Puerto Rican basketball player
- Custo Dalmau (born 1959), Catalan fashion designer
- Gastón Dalmau (born 1983), Argentine actor and singer
- Jordi Dalmau (born 1989), Spanish motorcycle racer
- José Luis Dalmau (born 1966), Puerto Rican politician
- Juan Dalmau Ramírez (born 1973), Puerto Rican lawyer and politician
- Lluís Dalmau, Catalan painter of the 15th century
- Martín Dalmau, (born c. 1974) Argentine politician
- Raymond Dalmau (born 1950), Puerto Rican basketball player
- Ricardo Dalmau (born 1977), Puerto Rican basketball player
- Richie Dalmau (born 1973), Puerto Rican basketball player