Moon Moon Sen married in 1978, to a descendant of the royal family of Tripura state. They have two daughters, actresses Raima Sen and Riya Sen. She has high regard for her husband, for his consistent support of her professional acting career.
Her late mother-in-law, Ila Devi, was the princess of Cooch Behar, and older sister of Gayatri Devi, the Maharani of Jaipur.
Moon Moon Sen was born into a Bengali family in Calcutta to popular Bengali actress Suchitra Sen and Dibanath Sen. Her father, of Ballygunge Place, was the son of one of the wealthiest businessmen of Calcutta, Adinath Sen. Her great grandfather Dinanath Sen was the Diwan or a Minister of the Maharaja of Tripura.
She was educated at Loreto Convent, Darjeeling and at Loreto House, Calcutta, then in a school in England and after coming back, she graduated from Loreto College, Calcutta. She received her masters in Comparative Literature from Jadavpur University, Kolkata.
As a child, Sen learnt drawing from Jamini Roy, one of India’s greatest artists.She loves paintings and collecting antiques. In an interview in 2000, she said she taught at Ballygunge Girls’ School for a year and then taught graphics at Chitrabani, a school teaching film techniques. She was also active in social work and even thought about adopting a baby, even before she was married. Sen taught English at a well known Boys’ school (Ballygunge Govt. High School) in Kolkata before joining films.