The suspect allegedly drove her here off Chicago Avenue and sexually assaulted her. He then fled the scene.
Police said the victim reported the incident about 8 p.m.
She was going to campus to sign up for classes when she was assaulted, police said.
Many of the international students who have moved into housing units at the University of California at Riverside are just getting the word about what happened.
"That's why we're sticking around together in groups," said Kelly Kim of South Korea. "We heard about that kind of incidents."
Jennifer Valadez, an employee at U.C. Riverside, said a man tried to break into a campus building and assault a woman just last week. But Valadez said she doesn't believe the incidents are related.
"It scares me to know that there are actually those kind of people around," Valadez said. "I don't want to be anywhere by myself at all."
The suspect was last seen driving away in an older model tan minivan with tinted windows.
Riverside police described the suspect as a Hispanic man in his early to mid-30s, 5-foot6 and 160 pounds with dark hair and mustache.
Anyone with information or who may have seen anything suspicious off Chicago Avenue near campus is urged to contact Riverside police at (951) 353-7126.