Castilho is a Portuguese surname. The Spanish version of this surname is Castillo. Notable people with the surname include:
Ana Augusta de Castilho (1860–1916), Portuguese activist Angelic del Castilho (born 1967), Surinamese politician António Feliciano de Castilho (1800–1875), Portuguese writer Carlos Castilho (1927–1987), Brazilian football goalkeeper Guilherme Castilho (born 1999), Brazilian footballer João de Castilho (also known as Juan de Castillo, 1470–1552), Spanish-Portuguese architect José Mauro Volkmer de Castilho (1946–1998), Brazilian scientist Iury Lírio Freitas de Castilho (born 1995), Brazilian footballer
See also Castilho, São Paulo, a municipality in Brazil Castilho (disambiguation)