Riya comes from a celebrity family, as her grandmother Suchitra Sen is one of the greatest Bengali actresses of Bengali films. Her mother Moon Moon Sen was also an actress and her father is a member of a Tropura Royal family. Her paternal grandmother Ila Devi, was the princess of Cooch Behar, whose younger sister Gayatri Devi is the Maharani of Jaipur. Before moving to Mumbai, she lived with her parents and sister Raima Sen, who is also an actress, in Kolkata.
Before entering show business, she studied at Loreto House and Rani Birla College, both in Kolkata, but dropped out of both institutions. She also briefly studied at the National Institute of Fashion Technology. Since her Bollywood debut, she has moved from Kolkata to Juhu in Mumbai.
Riya became a popular model when she appeared in numerous music videos for songs by popular singers, including Asha Bhonsle, Falguni Pathak, Jagjit Singh and Sonu Nigam. She was one of many Bollywood stars who appeared in Haath Se Haath Mila an anti-HIV/AIDS music video.
She is also an advertising model. A high point of her modeling career was when she replaced Lisa Ray as the Lakm Girl, but she has since been replaced by Yana Gupta. Her other notable assignments include Colgate, Limca, Vatika, Cadbury Dairy Milk Chocolate, and Margarita King. She has also appeared on the cover of a number of magazines. In 2004, she was featured partially nude in leading Indian photographer Dabboo Ratnani's[8] annual calendar, which is a major happening in the Indian glamor industry. She is the only female face to be featured on the calendar on four consecutive years (2004-2007).
As per her acting career is concerned, Riya Sen first appeared as a child artiste in the film Vishkanya, where she played the role of the young Pooja Bedi. At the age of 15 she was cast in a major role in Bharathiraaja's Tamil film Tajmahal. Her Bollywood film debut was supposed to have been in Love You Hamesha, opposite Akshaye Khanna, but the film was stalled and she ultimately made her debut in N. Chandra's low-budget comedy Style.
It was through style that she started crossing the ladder of success. Even her modeling career also nourished her image in Bollywood industry. It was not her family background that made her to reach top but it was her personal talent that brought this Bengali women in the top notch of the Bollywood actress list.