In her autobiography, entitled "Sabaray Ami Nami", Kanan Devi has observed that she was born illicitly. After the death of her adoptive father, Ratan Chandra Das, Kanan Devi and her mother were simply left to fend for themselves. Tulsi Banerjee, one of the prominent actors of that time, whom she called "Kaka babu" introduced Kanan Bala when she was only ten to Madan Theatres or Jyoti Studios where she was cast in a small role in Jaidev that was released in the year 1926. After that she did well in another film called Shankaracharya in the year 1927. Kanan Devi did at least five films with the Madan Theatres productions like Rishir Prem, Jorebarat, Bishnumaya and Prahlada, playing even male leads in the last two. She then worked with Radha Films from 1933-1936, then with New Theatres from 1937-1941, with MP Productions 1942-1948 and finally set up her own label Shrimati Pictures 1949-1965.
Her films with Jyotish Banerjee included Jaidev, Rishir Prem, Jorebarat, Vishnumaya, Kantahaar and Manomoyee Girls School. Her films with Prafulla Ghosh were Sree Gourange, Char Darvesh, Maa and Hari Bhakti. Others with Radha Film Company were Kanthahar, Krishna Sudama, Bishabriksha and Char Darvesh.
The films of New Theatres that was owned by Biren Sircar established her as a singer and her films ran to packed audiences. During her years with New Theatres, Kolkata from 1937, she played the lead in Barua's Mukti (1937), which was perhaps her finest performance, making her the studio's top star. Apart from Mukti, she did Vidyapati, Saathi, Street Singer, Sapera, Jawani ki Reet, Parajay, Abhinetri, Lagan, Parichay and Jawab.
Later, Kanan Devi came in contact with the music maestro Rai Chand Boral who not only coached and familiarized her in the Hindi language, but he experimented with many classical Western and Indian forms in his music. She received her initial musical training under Alla Rakha, one of the eminent Indian Singer. She was employed as a singer at the Megaphone Gramaphone Company, receiving further training under Bhishmadev Chatterjee. She later learnt the songs of Rabindranath Tagore under Anadi Dastidar. Her name was soon changed to Kanan Devi. Kanan Devi has worked with the biggest names in Bengali and Indian cinema from Kundan.Lal. Saigal, Pankaj Mullick, Pramathesh Barua, Pahari Sanyal, Chhabi Biswas and Ashok Kumar. Kanan Devi turned producer with Shrimati Pictures in 1949 and later launched the Sabyasachi Collective with the film Ananya (1949). Her own productions were mainly based on the stories of Sarat Chandra Chatterjee.
Kanan Devi, as the first lady of the Bengali movie, received many honours for her contribution to Indian cinema. She also received a honourary degree from Visva-Bharati University, the Padma Shri Awards in 1968 and the Dadasaheb Phalke Lifetime Award in 1976. She died on 17 July 1992 in Belle View Clinic, Kolkata when she was seventy-six years of age.