Sunny Deol was born as Ajay Singh Deol on 19 October 1956, in the village of Sahnewal in East Punjab, India in a Punjabi Jat family, to Bollywood actor Dharmendra and Prakash Kaur.

He has a younger brother Bobby Deol and two sisters Vijayta and Ajeeta who are settled in California, USA. Hema Malini is his step-mother. Actress Esha Deol and Ahana Deol are his half-sisters. His cousin Abhay Deol is also an actor.