She was born in 1934 as Ruma Ghosh. She hails from a Brahmo Bengali family. Her father was Satyen Ghosh (known as Montey Ghosh) and her mother was Sati Devi, a very talented woman. Sati Devi was a singer, a musician and India's first woman music director who worked with Uday Shankar at Almora, Prithviraj Kapur in Bombay and with Devikarani at Bombay Talkies. Sati Devi's younger sister Bijoya married film director Satyajit Ray. Thakurta had her formal education in many places including Santiniketan for a brief period. She was educated first in Loreto and then in Gokhale School and thereafter Sacred Heart School, Lahore. She was also one of the earliest child students of Uday Shankar Cultural Centre in Almora in its formative years where her mother had been a music teacher. Kishore Kumar married Ruma Ghosh in May 1952 in Bombay, and their son Amit Kumar was born the following year. The couple divorced in 1958. She settled in Calcutta and married Arup Guha Thakurta and had two children by him, Ayan and Sromana. In 1958 she set up Calcutta Youth Choir with Salil Chowdhury and Satyajit Ray.