The Royal Holloway University was evacuated overnight after multiple fires were started in a suspected arson attack.
Fire crews tackled several blazes, which were believed to be ignited deliberately in the university dormitories, police said.
Hundreds of students were led to safety after the evacuation at the Grade 1-listed campus in Egham at around 8pm on Thursday.
A helicopter and dogs were used in a search for the suspect and a man was detained nearby, the force said.
The 21-year-old man was arrested on suspicion of arson with intent to endanger life.
At least one room in the Gothic Revival-style Founder's building, completed in 1881, suffered "significant fire damage" but no one is believed to have been injured.
The university warned students at around 10pm that they would not be able to return to their rooms and said temporary accommodation would be arranged.
