The assault happened Tuesday morning near the college's Center for Media and Design at 26th Street and Olympic Boulevard, according to the Santa Monica Police Department.
The student reported that he was walking when an unidentified man came up to him and hit on the shoulder, causing him to fall to the ground.
Police have not identified the suspect, but he may have been a transient.
"I don't know if it's a lack of security or what, but there definitely are instances where there are houseless individuals around campus," said student Ignacio Meza. "It is a safety concern to have people that aren't members of the school, in general, kind of just roaming around freely and taking naps on campus."
The victim in Tuesday's alleged assault reported minor injuries.
Police say there is no ongoing threat to the campus.