William Adrián Castro Rosso (born 22 May 1962 in Mercedes) is a former Uruguayan footballer.
Castro had spells with Club de Gimnasia y Esgrima La Plata in the Primera División de Argentina and Cruz Azul in the Primera División de Mexico.
Castro made nine appearances for the senior Uruguay national football team from 1989 to 1991, and he was a member of the squad at the 1990 FIFA World Cup.