Detectives have released a CCTV image of a man they want to speak to in connection with the assault.
It happened in the early hours of Monday morning at the University of Bradford complex.
The 21-year-old was grabbed by the suspect as she was making her way home and attempted to push him away.
The man continued to grab hold of the victim’s wrists and sexually assaulted her.
The victim managed to get away after punching him in the chest. The suspect fled the scene.
The suspect is described as an Asian male, in his 20s, 5ft 6ins with a short trimmed beard. His clothing was distinctive: a black t-shirt with the words ‘Toyko, NYC and Paris’ emblazoned on his chest.
He was also wearing a hooded top.
Detective Inspector Damian Simpson, of Bradford District Safeguarding, said: “The victim was left shaken and extremely distressed as a result of this incident.
“I am releasing this CCTV image today and I hope that members of the public will recognise the male pictured as we continue to investigate.”
Call 01274 376607. Information can also be passed to Crimestoppers anonymously on 0800 555 111.