District additional superintendent of police Bhaskar Mukherjee said the incident took place on Wednesday night at Rajbati village when the woman's husband, a driver, was away.
The three accused, who were known to her and were from the same area, forcibly entered her home and allegedly raped her in the presence of her son.
She filed a complaint with the police yesterday and the accused - Shahbuddin, Md Shafi and Noor Islam were arrested last night.
Two years ago, a 20-year-old college girl was abducted, gangraped and murdered at Kamduni, near Barasat here. Hearing in the case is on.