Prakash Rai was born in Bengaluru, Karnataka on 26 March 1965 to a Tulu-speaking father, Manjunath Rai and a Kannadiga mother, Swarnalatha, in a lower-middle-class Family. His brother is Prasad Rai who is also an actor. He completed schooling at St. Joseph's Boys' High School, Bangalore and joined St. Joseph's College of Commerce, Bangalore. Prakash Rai changed his name to Prakash Raj based on prominent Tamil film director K. Balachander's advice; he is still called Prakash Rai in his home state, Karnataka.

Prakash Raj married actress Lalitha Kumari in 1994. They had two daughters, Meghana and Pooja, and a son Sidhu. The couple divorced in 2009. Praksh Raj is an atheist.

He married choreographer Pony Verma on 24 August 2010. They have a son, Vedhanth.

As an actor

Prakash began his acting career with Doordarshan serials such as Bisilu Kudure (Kannada) and Guddada Bhootha (Tulu and Kannada). He later took up supporting roles in Kannada films such as Ramachari, Ranadheera, Nishkarsha and Lockup Death. He was noticed for his dialogue delivery and histrionics. His breakthrough role came in Harakeya Kuri, directed by K. S. L. Swamy starring Vishnuvardhan, with whom he had acted in other films such as Mithileya Seetheyaru, Muthina Haara and Nishkarsha. His performance was noticed by Geetha, the lead heroine of the film, who introduced Prakash to her mentor K. Balachander, a Tamil director. He acted under the screen name "Prakash Rai" in Kannada films and was rechristened "Prakash Raj" by K. Balachander for his debut Tamil film Duet, which saw him playing his first major role.

Prakash re-entered Kannada films through Nagamandala in 1997, directed by T. S. Nagabharana, which was selected for the Indian Panorama in the International Film Festival in 1997. He was also a part of Mani Ratnam's stage show Netru, Indru, Naalai. In 1997, he acted in Mani Ratnam's biopic Iruvar. The movie dealt with the relationship between politicians M. G. Ramachandran and M. Karunanidhi, for which he won the National Film Award for Best Supporting Actor.

He starred in many Malayalam films in 1996: The Prince, Indraprastham and Oru Yathramozhi, the last released in 1997. He also acted in Pandippada, with Dilip in 2005, Thekkekara Superfast in 2003, Keerthichakra in 2006, Amal Neerad's Anwar and Shyamaprasad's sensational movie Elecktra in 2010. For most of his Mollywood movies, he will render his own voice. He will also be seen in his upcoming movie Achayans.

He acted in many Telugu films, including Antahpuram (1998) which earned him a National Film Award – Special Jury Award / Special Mention.

He played an important role in Venkat Prabhu's Saroja. In 2008, he produced a film titled Abhiyum Naanum and played an important character in it. He remade the movie in Kannada as Naanu Nanna Kanasu.

Since Wanted (2009), Prakash Raj has been a regular villain in Hindi language Bollywood movies, including Singham (2011), as Jaikant Shikre, Dabangg 2, as Bachcha Singh, Mumbai Mirror (2013), as Shetty, and the movie Policegiri, opposite Sanjay Dutt and Prachi Desai, as Nagori.

He acted with actor Kamal Haasan in the film Thoongaa Vanam (2015).

As a director

He took on the mantle of director with Naanu Nanna Kanasu, in Kannada in 2010, for which he was the joint producer. The film completed 125 days successfully in the theatres across Karnataka, becoming the biggest hit of the year. He was nominated for the Filmfare South "Best Director" category for his very first film.

He then directed the Telugu and Tamil bilingual film Dhoni. In 2014, he directed a multilingual film Oggarane (in Kannada), Ulavacharu Biryani (in Telugu) and Un Samayal Arayil (in Tamil). The Tamil and the Telugu versions didn't do any miracles at the box office, while Oggarane, the Kannada version became the runaway blockbuster hit of the year.^[29][30][31]

As a producer

Prakash became a producer beginning with the Tamil film Dhaya (2002), in which he was seen in the lead role with actress Meena. It earned him a Special Jury National Award for his performance. He later produced films in Tamil such as Naam (2003), Azhagiya Theeye (2004), Kanda Naal Mudhal (2005), Poi (2006), (starring Uday Kiran, his mentor K. Balachander and himself), Mozhi (2007), Velli Thirai and Abhiyum Naanum, which won many Tamil Nadu State Awards in 2008, and Inidhu Inidhu in 2010.

The first non-Tamil film that he produced was his directorial debut in Kannada Naanu Nanna Kanasu in 2010, a remake of his own Tamil production Abhiyum Naanum, for which he was the joint producer, along with his long-time Bengaluru theatre friend, Kannada director-producer B. Suresh.^[32] In 2011, he acted and jointly produced the Kannada film Puttakkana Highway, again with B. Suresh, who directed the film. It was a milestone in Prakash's production career since Puttakkana Highway won him the National Award for Best Regional Film for the year 2010–2011,^[33] and an award in the fourth Bengaluru International Film Festival of 2011.^[34]

His first Telugu production was the Tamil-Telugu bilingual Payanam (Gaganam) in 2011, starring superstar Nagarjuna Akkineni and himself in the lead role. In 2012, he produced two Tamil films; Mayilu and Dhoni. In 2013, he produced a Telugu-Tamil bilingual film; Gouravam. He produced a multilingual film Oggarane (Kannada), Ulavacharu Biryani (Telugu) and Un Samayal Arayil (Tamil) in 2014.^{[22][23][24][25]} Oggarane became a huge blockbuster hit that year.^{[26][27][28][29][30][31]}

Prakash Raj adopted the village Kondareddipalle in Mahabubnagar District, located in Telangana state.^[35]

Prakash has been involved in several controversies.

He was banned by Telugu film producers six times in the past. Prakash reacted to it by saying:

"If people who work with me say that I play hide and seek, why do they repeat me? Why am I in Mahesh's nine films out of his ten. Why don't you judge me with my work? How I go about it is not important. I don't go by the rules. I put my foot down, I don't take mediocrity. There are certain locations where I can come only at 12 in the morning. I don't go by the rules."^[36]

It was the first time that an actor was banned by the Telugu industry.^[37] Telugu film industry insiders interpret the ban as a conspiracy by several big heroes and producers. Problems started during the shooting of films such as Pavan Kalyan's Jalsa, NTR Jr's Kantri, and Parugu starring Allu Arjun.^{[37][38][39][40][41]}

There was controversy for his naked appearance in a sequence in his latest Telugu release titled Ongole Githa. The film got an "A Certificate" from the Censor Board. Prakash reacted by saying: "I did not shed my clothes for creating sensation, I had no plans to star in that sequence. The script demanded it; as an actor, I have to abide by the script. Director Bhaskar told me that it would be an 'important' sequence in the context of the film and I just carried out his instructions."^[42][43][44]

Several Kannada organisations staged protests in front of theatres since they felt that some of the dialogue in a scene in the Hindi film Singham, starring Ajay Devgan and Prakash were derogatory against the Kannadigas. The Karnataka Film Chamber of Commerce (KFCC) had demanded the deletion of all "objectionable" dialogue from the movie. The screening was stopped in major centres of Karnataka. The controversial scene starts off with Prakash threatening Ajay that he would bring 1,000 people from the Karnataka border to thrash him. Ajay (who plays Bhajirao Singham, a Maratha), retorts that one lion would suffice to shoo away a thousand dogs. The controversy assumes significance in the backdrop of the decades-old border dispute between Karnataka and Maharashtra. Kannada protesters also felt that Prakash, being a Kannadiga should have told the team that it is not right. Prakash reacted to it to the Kannada and the Telugu media by saying: "I am a Kannadiga myself and I love my mother tongue Kannada. I'm very proud of my community and would never deliberately do anything to hurt my people. How would I allow conversations that provide pain to people of Karnataka in any movie in which I am cast? There is nothing controversial about the dialogue. I am a Maratha in the movie, the controversy has started just because I am a Kannadiga and I used the word 'Karnataka border' in the film because the villain in the film stays in Goa, the Karnataka border."^[45][46][47] Finally the dialogue was removed, and the whole team of Singham including the director, Rohit Shetty, the production house "Reliance Big Entertainment" and Prakash apologised to all the Kannadigas; the issue was resolved.^{[48][49][50][51]}

• List of Bollywood villains