The 32-year-old victim, who is lodged in Tihar jail number 5, claimed that he had an argument with a jail official in May. He alleged that an inmate and the official demanded money from him and when he refused, he was threatened.
The victim was taken to a barrack, undressed and beaten up.
He was also sexually abused by the male inmates, he alleged.
The incident came to light when he was produced in a court.
On the directions of the court, police conducted medical examination which confirmed sexual abuse.
Following this a case was registered three days ago.
No one has been arrested.