Om Puri was born in Haryana in the city of Ambala. He originally aspired to join the army but changed his mind when he started acting in plays while at college. He joined the Film and Television Institute (FTII) in Pune and later graduated from the National School of Drama in 1973. In 1976, he made his debut with the Marathi film Ghasiram Kotwal (1976). Based on the highly influential play by Vijay Tendulkar, the film was directed by K. Hariharan and Mani Kaul in cooperation with graduates of the FTII. The play also starred another Mohan Agashe. He appeared in many films after that but his big moment came in 1980, when he starred in Govind Nihalani’s debut film, Aakrosh 1980. Puri played the role of a tribal who is accused of killing his wife. He won the Filmfare award for Best Supporting Actor for his performance. He then starred in several critically acclaimed films and even made an appearance in Richard Attenborough’s Gandhi (1982). In the same year, he acted in Shyam Benegal’s Arohan (1983) and won the National Film Award for Best Actor. He won the prestigious award again for his portrayal of a police officer in Ardh Satya (1983).
Puri also made a foray into international cinema and acted in numerous acclaimed films. He starred alongside Patrick Swayze in Roland Joffe’s City of Joy (1992) and received a British Academy of Film and Television Arts (BAFTA) nomination for best lead actor for the comedy drama East Is East (1999). His other notable English films are Wolf (1994), The Ghost and the Darkness (1996), Charlie Wilson's War (2007) and The Hundred-Foot Journey (2014), in which he starred alongside Helen Mirren.

Although primarily recognised as a serious actor, Puri has also starred in comedy films. One of his most memorable comic performances is in the cult classic Jaane Bhi Do Yaaro (1983).
Puri has also appeared in TV shows like Second Generation, Jewel in the Crown, Bharat Ek Khoj and Aahat.

He has been the recipient of numerous awards throughout his illustrious career. In 1990, he received the Padma Shri and in 2004, he was made honorary Officer of the Order of the British Empire (OBE) in recognition of his contribution to the British film industry.