Born on October 13, 1911 at Bhagalpur, Bihar, as Kumudlal to a famous lawyer, Kunjlal Ganguly, whose family migrated from Nadia to Khandwa some hundred years ago. Kumudlal was a

brilliant student, who after finishing his B. Sc. from Robertson College, Jabalpur, went to study law at Presidency College, Calcutta so that, according to him, "his grandpa's books may be used". As a science student, he developed a flair for photography and really wanted to become a technician. He used to visit New Theaters, Calcutta, and left Calcutta for Bombay in 1934, to meet the veteran director Himanshu Raj who persuaded Ashok to learn film photography from Josef Wirsching, the talented German cameraman for Bombay Talkies. He was appointed a Laboratory Assistant and that started the cine journey of Kumudlal, later becoming actor Ashok Kumar.

He had a small role in Jawani ki Hawa (1935). He was forced to act by a veteran director Himanshu Rai. His first film Jeevan Naiyya (1936) had a different leading man who suddenly fell ill. In need of an immediate fill-in, Rai approached Ashok Kumar to play the lead. Hesitatingly, Ashok Kumar agreed, and was the male lead opposite Devika Rani in (1936). His next movie Achhut Kanya proved to be a big hit and established him as a successful actor. Ashok Kumar saw a success unmatched in this period. He had three major hits, Kangan, Bandhan and Jhoola, in a row. His Kismet ran for 4 years and was a record.

In early period of his acting career Ashok Kumar played sensitive hero in films till Kismet changed everything. Then came a series of thrillers including Mahal (1949), Samadhi (1950), Sangram (1950) and Howrah Bridge (1958) which are considered classics today: Sensitive performances in more meaningful films like Parineeta (1953), Naubahar, Savera, Ek Hi Raasta and Bandini continued establishing him as a polished actor. As the things changed with time and age, Ashok Kumar shifted to playing characters. He played varied and often complex characters. Gumrah, Kanoon, Mere Mehboob, Jewel Thief, Aashirwaad, Mili, Khubsoorat, Victoria No 203 and Shaukeen. Over six decades in the industry, Ashok Kumar still works. He also made his career as a producer. Some of his produced movies under the Bombay Talkies banner were Mahal, Majboor, Mashaal, and Ziddi etc. He then started Ashok Kumar productions, which made a few films like Maa, Kalpana and Meri Soorat Teri Aankhen. He later stopped making films and concentrated on acting. His last film was Return of Jewel Thief.

He joined his daughter Preeti to establish 'Ashok Kumar Academy of Acting' which they run together.