He accepted pivotal supporting roles in Tamil films such as Aayiram Vilakku, Uchithanai Muharnthaal, Nanban, Thalaivaa and Raja Rani. In Nanban, he played a college professor and won the Best Supporting Actor awards at the Filmfare, Vijay and SIIMA ceremonies, while in Thalaivaa, Raja Rani, Mirchi and Chennai Express he played father characters. Sathyaraj and Manivannan worked together for the last time in Nagaraja Cholan MA, MLA, which was Manivannan's 50th and last directorial venture before his death. A sequel to Amaidhipadai, it was also the 200th film of Sathyaraj and became a box office bomb.

Sathyaraj was born as Rangaraj on 3 October 1954 to Subbaiyan and Nathambal, with two younger sisters, namely Kalpana Mandradiar and Roopa Senapathy (wife of Dr. Periannan Senapathy). He is an ardent fan of M. G. Ramachandran. Sathyaraj completed his primary school education in St Mary's Convent school, Coimbatore and later studied for tenth standard from Suburban High School, Ramnagar, Coimbatore. He went to Government Arts College, Coimbatore for a Bachelor of Science degree in Botany.

Sathyaraj's dream was to become a film actor, but his mother was against it and forbid him to join cinema. In 1976, in spite of his mother's opposition, he left Coimbatore to enter the Tamil film industry based in Kodambakkam, Chennai.

In his early career between 1978 and 1982, the negative roles he played were often henchman to the main villain M. N. Nambiar and other villains and his role would be minuscule, while the main lead was Sivaji Ganesan, Jai Shankar, Kamal Hassan or Rajinikanth. His college friend Manivannan directed Sathyaraj for the first time in the Tamil film January 1 in 1984, where Sathyaraj had a supporting role. Manivannan directed Sathyaraj in about 25 films from 1984 to 2013 and of them 18 had Sathyaraj as the main lead. His screen space as a villain increased after Irupatthi Naalu Mani Neram (1984), directed by Manivannan, in which Sathyaraj's role was on par with that of lead actor Mohan. His acting skills in the film were noticed by many and he became famous among the Tamil film audience. Sathyaraj also felt that his villainous roles in Nooravathu Naal and Anbin Mugavari, both again directed by Manivannan, had better footage than that of Vijayakanth's and Mohan's. Sathyaraj started receiving offers to act as the hero in Tamil films from 1985. Directors were reluctant to cast him as the protagonist as his second film as a lead actor Iravu Pookkal (1985) was not a success. Most of the films he was part of were of the action genre in this period.

Sathyaraj was married to Maheswari in 1979, niece of Producer Madhampatti Sivakumar and the couple has a daughter Divya and a son Sibiraj. His son Sibiraj is also an actor. He is an atheist.

In Needhiyin Nizhal (1985), which featured Prabhu in the lead role, Sathyaraj had a minuscule supporting role and played second fiddle to the main villain M.N. Nambiar, but by 1988, Sathyaraj had established himself as a leading actor and in Chinna Thambi Periya Thambi, in which Prabhu and Sathyaraj were cast in the starring role, Prabhu's character played second fiddle to Sathyaraj's character. He played a bespectacled leading man in the commercially successful Ganam Courtaar Avargaley and his performance was critically acclaimed and it established him as a versatile actor.

In the 1986 film Kadalora Kavithaigal, he played the lead romantic role and Behindwoods said: "Sathyaraj broke his image of an action hero and came up with a rollicking performance. He is the real star of the film." He received appreciation for playing his role in Mr. Bharath (1986), which revolved around the conflict between father, played by Sathyaraj and son (Rajinikanth). Sathyaraj acted as Rajinikanth's father in the film, though he was in fact 4 years younger than Rajinikanth. Manivanan, being friends with Sathyaraj, kept casting him in pivotal roles in his directorial ventures, regularly showcasing different emotions from Sathyaraj in films such as Vidinja Kalyanam, Palaivana Rojakkal and Muthal Vasantham. After Kadalora Kavithaigal, Sathyaraj had box office hits as the lead hero between 1986 and 1988 such as Kadamai Kanniyam Kattupaadu, Makkal En Pakkam, Mandhira Punnagai (in which he had dual roles), Poovizhi Vasalile, En Bommukutty Ammavuku, Chinappadas and Annanagar Mudhal Theru. Manivanan from 1987 onward started casting Sathyaraj in positive roles and their combination had box office hits like Jallikkattu, Chinna Thambi Periya Thambi, Ganam Kortaar Avargale and Chinnappadas in this period. Sathyaraj received the Best Tamil Actor award in Filmfare Awards South for his performance in Vedham Pudhithu (1987).

Sathyaraj and Manivannan shared a close friendship since college and became frequent collaborators in notable films in Tamil cinema. The Hindu wrote: "His (Manivannan's) friendship with actor Sathiyaraj translated to several memorable moments on screen. Manivannan...along with Sathyaraj epitomised on screen what is colloquially known in Tamil as "nakkal" (snideness)". According to Behindwoods.com, Manivannan (as the director) and Sathyaraj had 12 consecutive hit films together beginning from 1987 to 1994; Jallikattu, Chinna Thambi Periya Thambi, Ganam Kortaar Avargale, Manidhan Marivittan, Ullathil Nalla Ullam, Vazhkkaichakkaram, Pudhu Manithan, Therku Theru Machan, Government Mappillai and Amaidhi Padai. About working with Manivannan, he has said that it "is a pleasure. There's no script, no dialogue sheet. It's all in his head. But, he extracts great performances". Sathyaraj and Manivannan also acted together in several films directed by other Directors.

His 99th film was Dravidan and his 100th film was Vaathiyaar Veettu Pillai, but the latter fared better at the box office. After 1988, he had very few unsuccessful film such as Jeeva, Madurai Veeran Enga Saami, Pangali, Magudam and Kattalai in this period as he became selective of choosing his roles as main lead hero. In the 90s, he attempted more films of comedy and action genres and occasionally did romantic films. Many of them were commercially successful, such as Velai Kidaichuduchu, Airport, Veera Padakam, Nadigan, Pudhu Manithan, Rickshaw Mama, Walter Vetrivel, Thai Maaman and Azhagarsamy. Sathyaraj played a dual role as father and son in the box office hit Amaidhi Padai, which is considered among his best performances. With regard to the film, he has stated: "I have no words for that film, as it took me to the next level as an actor". He also said that he almost did not sign up for the film as it was a negative character and he had moved away from negative roles and "gained some respectability" with films such as Poovizhi Vaasalile, Vedham Pudhidhu and Walter Vetrivel. After Thai Maaman became successful in 1994, the same team of Sathyaraj and Director Guru Dhanapal decided to do their next venture Maaman Magal in 1995, which was also a moderate hit. He directed his first film in 1995 Villadhi Villain, which had him in three distinct roles and it was a successful project.

Films in the 2000s with Sathyaraj in the lead role that fared well at the box office were 6'2, Vanakkam Thalaiva, his 170th film Kurukshetram (2006), Periyar and Thangam. He received the Vijay Award for Best Actor for Onbadhu Roobai Nottu in 2007 and was also nominated for his performance in Periyar in the same year, in which he portrayed the life of social reformer and rationalist Periyar E. V. Ramasamy. About the role he said, "I myself being a rationalist, I found it easy to portray his character on screen. His principles and ideologies, like fighting for women's liberation and untouchability, have influenced me to a great extent".

His pairing opposite Actress Kushboo and Meena became popular in this decade. The box office hits of the pair Kushboo-Sathyaraj include Nadigan, Rickshaw Mama, Bramma, Kalyana Galatta, Malabar Police, Suyamvaram and Unnai Kann Theduthey, whereas Thozhar Pandian and Veeranadai were not successful at the box office. The on-screen pair of Sathyaraj-Meena together had average grossers such as Thai Maman, Maman Magal, Valal and later in 2003 with Aalukkoru Aasai. His chemistry with actors Goundamani and Senthil has been well received and appreciated by the public and hence they have appeared in many movies together from Vaazhkai Sakkaram in 1990 to Thangam in 2008.

He ventured into Telugu cinema after long time as a supporting actor in Sankham in 2009 and later did Mirchi in 2012, both of which were successful. He also entered Malayalam cinema with Aagathan in 2009. He played the critically acclaimed role of Kattappa in Baahubali: The Beginning (2015) and has reprised the role in the sequel Baahubali: The Conclusion (2017).

In 2011, he had a brief career as a television host for the game show Home Sweet Home on STAR Vijay. He has also served as a brand ambassador for Pothys and Kumaran Jewelry Shop.

Sathyaraj was also personally close to Manivannan. He said: "I still Reminisce about the beautiful moments that I had with...Manivannan, a genius of a person. In fact, he is the one who taught me many things in life, and changed me, I became a good human from being just an actor. Every day, we used to have conversations over the phone on a wide range of topics. It was a 30-year relationship. No one could understand me the way he did". Manivannan died in 2013 and Sathyaraj has said that just 24 hours before his death they had discussed their next project and that he narrated him a story.

In 2015, at the age of 60, the media and public at large rechristened him as Kattappa, as he received nationwide popularity for his role in India's biggest motion picture Baahubali: The Beginning. Since the time he made his debut as junior artiste at 24 years of age, he had been wanting to do a historical or a folklore film and it was his long cherished dream. He quoted in an interview in 2015: "I am a great fan of MGR who is popular in folklore films, like NTR in Telugu movies. My dream of doing a folklore at 24 has been realised at 60 through Rajamouli. I played Rajinikanth's father when I was 31 and Rajini was 35, so I never cared for age..it never mattered to me."