Valencia High School is a public secondary school located in the neighborhood of Valencia in the city of Santa Clarita, California, United States. It is a part of the William S. Hart Union High School District.

Valencia is a neighborhood in Santa Clarita located within Los Angeles County, California. It is one of the four unincorporated communities that merged to create the city of Santa Clarita in 1987. It is situated in the western part of Santa Clarita, stretching from Lyons Avenue to the south to north of Copper Hill Drive, and from Interstate 5 east to Bouquet Canyon and Seco Canyon Roads. Valencia was founded as a master-planned community with the first development, Old Orchard I, built on Lyons Avenue behind Old Orchard Elementary School.