Sen was born in Hyderabad, Andhra Pradesh to a Bengali Kayastha Hindu family. Her father, Shubeer Sen, is a former Indian Air Force Wing Commander and her mother, Subhra Sen, is a fashion artist and jewelry designer. She has a brother, Rajeev Sen. She was born in St. Theresa’s hospital, Hyderabad, and grew up in New Delhi. She attended school at the Air Force Golden Jubilee Institute.
In 2000, she adopted a daughter, named Renée. On 13 Jan, 2010 she adopted a three-month-old girl and named her Alis ah