The victims used to attend coaching classes at the accused's house in central Delhi's Rajinder Nagar.
The accused, Sudhir, was arrested after a 14-year-old boy studying in Class IX told his parents that he was sexually assaulted by the tutor, police said.
The parents informed the police and Sudhir was arrested after the boy's medical examination confirmed the sexual assault.
During investigation, it was found that three more teenage students were assaulted by Sudhir.