Rajkumari's first film with them was a Hindi-Gujarati bilingual called Sansar Leela Nayi Duniya. She got important roles in films like Aankh Ka Tara and Turki Sher (1933). She was the heroine Bhakt Ke Bhagwan and Insaaf Ki Topi (1934). In those days she often acted opposite Zakaria Khan (late actor Amjad Khan's father, whose screen name was Jayant). She also used to sing for popular music director Lallubhai. He gave music to films starring Rajkumari ji like Nai Duniya alias Sacred Scandal(1934) (Sansaar Leela in gujrati version), Laal Chitthi alias Red Letter(1935), Bombay Mail(1935), Bambai Ki Sethaani (1935)and Shamsheer-e-Arab(1935). She began getting fed up with having to watch on her figure and decided to stick to just singing as a career. After she quit Prakash Pictures, she began playback singing for actresses like Ratnamala, Shobhana Samarth, etc. and soon she became the First Female Playback Singer of Indian Cinema.
She sang many Gujarati and Punjabi songs. Even though she was not trained to sing, she was very good at picking up what her composers taught her. They thought she was a trained singer! She was able to also establish herself as a classical singer and excelled in singing and voice production within the framework of classical forms of thumri and dadra. Among her peers were Shamshad Begum, Zohrabai Ambalewali, Juthika Roy, Zeenat Begum, etc. Both Shamshad and Zohrabai had resounding voices with a high range, while Rajkumari had a soft voice with a small range. She sang quite a few songs with Mukesh. She did not get much opportunity to sing with Mohammed Rafi - mainly because Lata Mangeshkar was a fast upcoming singer at the time. She sang with Noor Jehan in Naukar (1943). She never sang with K. C. Dey, but she did sing songs composed by him, as well a his nephew, Manna Dey.
Rajkumari was married very late in life. Her husband was V.K. Dubey who was from Benares (Uttar Pradesh) where he spent a lot of his time (because he owned a shop there), while she settled in Bombay. He later joined her in Bombay. Later, she would go on to sing songs for Neel Kamal, a Raj Kapoor and Madhubala starrer, and Hulchul (1951); but her two most famous films would be Bawre Nain (1950) (where she sang for Geeta Bali) and Mahal (1949), where she sang for the Indian actress Madhubala (Rajkumari actually sang for Vijayalaxmi, Lata sang for Madhubala). By this time, however, Lata Mangeshkar and Asha Bhosle had shot to fame, relegating most other female singers in the industry to the sidelines.
She sang her only song for O. P. Nayyar in the 1952 movie Aasmaan which was his debut movie, Jab Se Pee Piya Aan Base. The story goes that he was considering Lata Mangeshkar for the song. (Rest of the songs of the movie are sung by Geeta Dutt and C. H. Atma). When somebody told this to Lata, she said something about him which led to a misunderstanding. Angered O. P. Nayyar made Rajkumari sing this song and never repeated her. He never used Lata to sing for him as well. Rajkumari endured a long dry spell until music director Naushad spotted her singing in the chorus for his background score for Pakeezah (1972). Naushad was much taken aback by this, having greatly respected her in her heyday, and heartbroken to hear that she was reduced to singing in the chorus to make ends meet. As a result, he gave her an entire song to herself in Pakeezah, Najariya ki Mari. Her last film song was recorded for R. D. Burman in the film Kitaab, Har Din Jo Beeta. Rajkumari also appeared in a British TV programme called 'Mahfil' on Channel 4, a Samandar Films prouduction, produced by Firdous Ali and Mahmood Jamal. In this programme she sang a set of her famous film songs and ghazals; the caption on one of the songs, 'Yeh raat phir na aayge', from the film Mahal, cites that the song was pictured on Zohra (and not Madhubala or Vijayalaxmi). The programme was aired on 24 March 1991. Rajkumari died in poverty in early 2000.