Dharmendra was born Dharam Singh Deol in Nasrali, a village in Ludhiana district, Punjab on 8 December 1935 to Kewal Kishan Singh Deol and Satwant Kaur in a Punjabi Jat family. His ancestral village is Dangon, near Pakhowal Tehsil Raikot, Ludhiana.

He spent his early life in the village of Sahnewal and studied at Government Senior Secondary School at Lalton Kalan, Ludhiana, where his father was the village school’s headmaster. He did his intermediate studies at Ramgarhia College, Phagwara in 1952.

Dharmendra’s first marriage was to Parkash Kaur at the age of 19 in 1954. He had two sons from this marriage, Sunny and Bobby, both successful film actors, and two daughters, Vijeeta and Ajeeta.

Dharmendra was the winner of Filmfare magazine’s nationally organised new talent award and went to Mumbai from Punjab, to work in the movie promised, being the award winner, but the movie was never made. He later made his debut with Arjun Hingorani’s Dil Bhi Tera Hum Bhi Tere in 1960. He had a supporting role in the film Boy Friend in 1961, and was cast as the romantic interest in several films between 1960 and 1967.

He worked with Nutan in Soorat Aur Seerat (1962), Bandini (1963), Dil Ne Phir Yaad Kiya (1966). and Dulhan Ek Raat Ki (1967); with Mala Sinha in Anpadh (1962), Pooja Ke Phool (1964), Baharen Phir Bhi Aayengi (1966), and Ankhen (1968); with Nanda in Akashdeep (1965); and with Saira Banu in Shaadi (1962) and Ayee Milan Ki Bela (1964). Dharmendra formed a successful pairing with Meena Kumari and shared the screen in 7 films namely Main Bhi Ladki Hoon (1964), Kaajal (1965), Purnima (1965), Phool Aur Patthar (1966), Majhli Didi (1967), Chandan Ka Palna (1967) and Baharon Ki Manzil (1968). He had a solo hero role in Phool Aur Patthar (1966), which was his first action film. It has been speculated for a long time that Meena Kumari and Dharmendra had an intimate relationship in the 1960s. Meena Kumari helped him to establish himself among the A-listers of that time. Phool Aur Paththar became the highest-grossing film of 1966 and Dharmendra was nominated for Filmfare Award for Best Actor for the first time. His performance in Anupama was critically acclaimed. He was given a souvenir at the 14th National Film Awards in recognition of his performance in the film. He did romantic roles in films like Aaye Milan Ki Bela, Aaya Sawan Jhoomke, Mere Humdum Mere Dost, Ishq Par Zor Nahin, Pyar Hi Pyar and Jeevan Mrityu. He did suspense thrillers like Shikar, Blackmail, Kab Kyun Aur Kahan and Keemat. He received a Filmfare Best Actor nomination for an action hero role in the 1971 hit film Mera Gaon Mera Desh. Having played romantic as well as action hero parts, he began to be called a versatile actor by 1975.

In 1983, Dharmendra set up a production company known as Vijayta Films. In its maiden venture Betaab, released in 1983,Vijayta Films launched Sunny Deol as the lead actor. The movie was the second highest-grossing movie of the year. In 1990 he produced the action film Ghayal, also starring Sunny. The film won seven Filmfare Awards, including the Best Movie Award. It won the National Film Award for Best Popular Film Providing Wholesome Entertainment. Dharmendra then launched the career of his younger son, Bobby, in 1995 in Barsaat.

In 1997, he received the Filmfare Lifetime Achievement Award. While accepting the award from Dilip Kumar and his wife Saira Banu, Dharmendra became emotional and remarked that he had never won any Filmfare award in the Best Actor category despite having worked in so many successful films and nearly a hundred popular movies. Speaking on this occasion Dilip Kumar commented, “Whenever I get to meet with God Almighty, I will set before Him my only complaint – why did you not make me as handsome as Dharmendra?”.

Dharmendra served as a Member of the Indian Parliament (Lok Sabha) representing Bikaner in Rajasthan from 2004 to 2009 on behalf of the Bharatiya Janata Party. During his election campaign in 2004, he made an offensive remark that he should be elected dictator perpetuo to teach “basic etiquette that democracy requires” for which he was severely criticised. He rarely attended Parliament when the house was in session, preferring to spend the time shooting for movies or doing farm-work at his farm house.

His most successful pairing was with Hema Malini, who went on to become his wife. The couple played together in many films including Raja Jani, Seeta Aur Geeta, Sharafat, Naya Zamana, Patthar Aur Payal, Tum Haseen Main Jawaan, Jugnu, Dost, Charas, Maa, Chacha Bhatija, Azaad and Sholay. His most notable acting performances include Satyakam with Hrishikesh Mukherjee, and Sholay, which is listed by Indiatimes as one of the “Top 25 must see Bollywood films of all time”. In 2005, the judges of the 50th annual Filmfare Awards awarded Sholay the special distinction of Filmfare Best Film of 50 years.

After a four-year hiatus from acting since 2003, he reappeared in films as a character actor in 2007 in Life in a… Metro and Apne; both films were both critically and commercially successful. In the latter, he appears with both his sons, Sunny and Bobby for the first time. His other release was Johnny Gaddaar. In 2011, he starred alongside his sons again in Yamla Pagla Deewana, which was released on 14 January 2011.

In 2011, Dharmendra replaced Sajid Khan as the male judge of the third series of popular reality show India’s Got Talent.

On 29 July 2011, India’s Got Talent aired on Colors with Dharmendra as the new judge and surpassed the opening ratings of the previous two seasons.

A sequel, Yamla Pagla Deewana 2, was released in 2013. He appeared with his daughter Esha Deol in his wife (Hema Malini)’s directorial venture, Tell Me O Khuda in 2011. In 2014, he played a double role in the Punjabi film, Double Di Trouble.

In 2019, Dharmendra’s grandson and Sunny Deol’s son Karan Deol made a debut with Pal Pal Dil Ke Pas.