Khwaja Ahmad Abbas was born in Panipat, Punjab, British India (now Haryana, India). He was born in the home of celebrated Urdu poet Khwaja Altaf Husain Hali, a student of Mirza Ghalib. His grandfather Khwaja Gulam Abbas was one of the chief rebels of the 1857 movement, and the first martyr of Panipat to be blown from the mouth of a cannon. Abbas's father Ghulam-Us-Sibtain graduated from Aligarh, was a prosperous businessman, who modernised the preparation of Unani medicines. Abbas's mother Masroor Khatoon was the daughter of Sajjad Husain, an enlightened educationist. Abbas took his early education in Hali Muslim Highschool, which was established by his great grand father Hali. He had his early education till 7th in Panipat. He was instructed to read the Arabic text of the Quran and his childhood dreams swung at the compulsive behest of his father. Abbas completed his matriculation at the age of fifteen. He did his B.A. with English literature in 1933 and LL.B. in 1935 from Aligarh Muslim University. Abbas began his career as a journalist, when he joined National Call, a New Delhi based paper after his finishing his B.A.. Later while studying law in 1934, started Aligarh Opinion, India's first university students' weekly during the pre-independence period. After completing his education at Aligarh, Abbas joined the Bombay Chronicle. He occasionally served a film critic, but after the film critic of the paper died, he was made the editor of the film section.
K.A.Abbas entered films as a part time publicist for Bombay Talkies in 1936 to whom he sold his first screenplay Naya Sansar (1941)'. He started writing scripts for other directors, Neecha Nagar (1946) for Chetan Anand and Dr. Kotnis Ki Amar Kahani (1946) for V. Shantaram. In 1945, he made his directorial debut with a film based on the Bengal famine of 1943, Dharti Ke Lal (1945) for the Indian People's Theatre Association (IPTA).
In 1951 Abbas founded his own production company called Naya Sansar, which consistently produced films that were socially relevant including, Anhonee (1952), Munna(1954) and the National Award winner, Shehar Aur Sapna (1964).
A prolific writer, and novelist, during his illustrious career spanning five decades, Abbas wrote over 73 books in English, Hindi and Urdu. Abbas was considered a leading light of the Urdu short story. His best known fictional work remains 'Inquilab', based Communal violence, which made him a household name in Indian literature. Like Inquilab, many of his works were translated into many Indian, and foreign languages, like Russian, German, Italian, French and Arabic. Abbas interviewed several renowned personalities in literary and non-literary fields, including the Russian Prime Minister Khrushchov, American President Roosevelt, Charlie Chaplin, Mao-Tse-Tung and Yuri Gagarin. He went on to write scripts for Jagte Raho, and most of prominent Raj Kapoor films including Awaara (1951), Shri 420(1955),Jagte Raho(1956), Mera Naam Joker(1970), Bobby (1973) and Henna (1991). He directed the debut film of Amitabh Bachchan Saat Hindustani (1969). His autobiography, I Am not an Island: An Experiment in Autobiography, was published in 1977.
Abbas died on 1 June, 1987 in Mumbai.
Abbas received the 1963 President's Gold Medal for Shehar Aur Sapna which also won the 1964 National Film Award for Best Film. His film Do Boond Paani(1971) received Nargis Dutt Award for Best Feature Film on National Integration.