Before UC Riverside was established, the land the current university sits on was used by the University of California system as its Citrus Experimentation Station. The same orange groves and plant sites are still used for research to this day. By the 1950s, California's growing population made it necessary for the campus to become a full-fledged member of the UC system, and it was so designated in 1959. UC Riverside began enrolling graduate students in 1961.
UC Riverside has been a member of The Big West since 2001. At the Division II level, the Highlanders won four national championships (baseball in 1977 and 1982, women's volleyball in 1982 and 1986) before making the transition to The Big West and Division I. To date, UC Riverside has won 10 Big West postseason championships and five Big West regular-season titles.