Casas is a Spanish surname. Notable people with the surname include:
Gastón Casas (born 1978), Argentine footballer
Javier Casas (born 1982), Spanish footballer
Negro Casas (born 1960), Mexican professional wrestler
Penelope Casas (1943–2013), American food writer
Queralt Casas (born 1992), Spanish women's basketball player
Ramon Casas i Carbó (1866–1932), Spanish artist
Yancarlo Casas (born 1981), Peruvian footballer