She was born in Kalka, Haryana, and educated at Sacred Heart Convent in Lahore, and then in Nainital. After graduating from school, she taught at the Gokhale Memorial School in Calcutta. In Allahabad, she met her future husband, Asaf Ali,a prominent Congressman who was 23 years older than her. They were married in 1928 against parental opposition on the grounds of both religion and age.
Her marriage plunged her into the midst of the freedom struggle, with which her husband was deeply involved. Her first major political action was during the Salt Satyagraha in 1930, when she addressed public meetings and led processions. She was promptly thrown into jail by the British, for being a 'vagrant', and sentenced to one year's imprisonment. A few months later, most political prisoners were released on the signing of the Gandhi-Irwin pact, but since she was not a political prisoner, she was not released. Her women co-prisoners in Lahore jail refused to leave jail without her, and finally did so only on Gandhi's intervention. After a public agitation for, she was released from prison.
She was arrested again in 1932 and put in Tihar Jail, where she went on a hunger strike against the treatment of political prisoners. Her protest caused an improvement in conditions, but she herself was moved to solitary confinement in Ambala. Eventually released, she dropped out of the national movement for 10 years.
In 1942 she went to the Bombay Congress Session with her husband, and was present at the passing of the Quit India resolution on 8th August. When the Congress leaders were arrested on the day after this resolution was passed, Aruna presided over the flag-hoisting ceremony at Gowalia Tank Maidan in Bombay, where the enormous assembly was tear gassed, lathi-charged and fired upon. She became a full-time activist in the Quit India movement, eventually going underground to evade arrest. Her property was seized by the Government and sold.
She became editor of Inquilab, the monthly magazine of the congress, along with Ram Manohar Lohia and in its 1944 issue she advised freedom fighters not to "allow any academic and therefore futile arguments on questions like violence and non-violence to divert attention from the stern realities of today & I want every student and youth to think and feel as soldiers of the revolution that is to come."
The Government meanwhile announced a Rs. 5000 reward for her capture. She fell ill and hearing of this Gandhi advised her to surrender: "I have sent you a message that you must not die underground. You are reduced to a skeleton. Do come out and surrender yourself and win the prize offered for your arrest. Reserve the prize money for the Harijan cause." However, Aruna surrendered herself only when the warrants against her were cancelled on 26th January 1946.
Aruna Asaf Ali also worked in the women's league which was affiliated to the All India Women's Conference. In 1954 she helped to
establish the National Federation of Indian Women (NFIW), the women's wing of
the Communist Party of India. The NFIW was meant to be a radical alternative
to existing women's organizations, and one that would reach beyond a middle
class membership.
After Independence she turned to social work, and served as the first mayor of Delhi. After her term, she left public office and spent the rest of her life working with women and the rural poor. She was posthumously awarded India's highest civilian award, the Bharat Ratna, and was honoured with a stamp issued by the Indian Postal Service in 1998.