The accused knew the girl and had proposed to her but she declined, police said.
On December 29 the accused allegedly entered her house in Juhu forcibly and tried to molest her; when she resisted he assaulted her, police said.
The victim approached Juhu police and lodged a complaint yesterday, following which he was arrested last night under section 354 (assault or criminal force on woman with intent to outrage her modesty) of IPC.
A local court later granted him bail.