Police have arrested a 33-year-old Chinese man with a sexual fetish for the alleged rape, which he also videoed, of an 18-year-old university student in Bangkok.

The young victim told police she met the man, identified as Su Xing Rui, on the 6th floor of MBK centre in Pathum Wan district on the evening of Nov 19.

The man acted like a tourist, talking to her in Chinese, a language she was learning, and invited her back to a hotel on Petchaburi road. The young woman alleged he held her there against her will and forced her to participate in making a sex video with him, police said.

She went home devastated. The suspect later texted her, asking her to do it again, she said. She decided to tell her family and filed a complaint at Phaya Thai police station.

Police set up a sting, making an appointment for the woman to supposedly see the suspect again. Mr Su asked her to bring another man with her for "fancy sex", IDMB commander Pol Maj Gen Theeradech Thammasuthee said on Tuesday. 

An officer dressed as a wrestler waited to meet the suspect in a hotel room in Ratchathewi district. Six other officers concealed themselves inside the room. The officers emerged from their hiding places and arrested Mr Su after the disguised officer gave an agreed signal, the police commander said.

The arresting officers impounded his phone, along with many upskirt photos and sadistic sex videos he took with other victims, and a rope he allegedly used for his sexual fetish activities.

The suspect initially denied all charges. He was held in custody at Phaya Thai police station for further investigation.