Padayappa is a mechanical engineer who returns to his village to attend his sister's engagement to Suryaprakash, the son of their maternal uncle Rajarathnam.

Suryaprakash's sister, Neelambari, also falls in love with Padayappa, making Vasundhara scared to admit her feelings.

Within days, Suryaprakash marries Ramalingam's daughter Meena without the villagers' knowledge, craving their newfound wealth and status.

While Padayappa sets to clean his land for agriculture, Ramalingam's spy finds small rocks, and he discovers that a hill on that property is solid granite, which is very valuable.

He starts the granite business, becoming wealthy and taking over the chieftain position of his father while his family settles in a new mansion and regains their respect.

Suryaprakash brings Neelambari to his home, but she locks herself in her room, and refuses to come out, watching Padayappa's wedding video on repeat.

Suryaprakash also has a son, Chandraprakash alias Chandru, who studies at the same college as Padayappa's elder daughter, Anitha.

Padayappa discovers that Chandru really did fall in love with Anitha, even though he was only initially pretending to do so on Neelambari's orders.

When Padayappa takes Chandru and Anitha to the temple to get married, Neelambari and Suryaprakash give chase to stop them.

Armed with a machine gun, Neelambari reaches the temple where Chandru and Anitha are married, and tries to kill Padayappa.

Instead, Padayappa saves her life by preventing a bull from attacking her, while at the same time dodging the bullets she fires at him.

[16] The film was produced by K. Sathya Narayana, M. V. Krishna Rao, and H. Vittal Prasad under their production banner, Arunachala Cine Creations,[17] along with P. L. Thenappan as co-producer.

[21] Ravikumar revealed that the makers could not sign Simran due to her busy schedule and Meena was also considered for Vasundhara's role.

[27] Ramesh Kanna was chosen to play Murugesan after Rajinikanth was impressed with his performance in Unnidathil Ennai Koduthen (1998).

[35] Writing for PopMatters, Ranjani Krishnakumar noted that Padayappa underlined Rajinikanth's political manoeuvres, evident when his character's lover sings "Kaadhal therdhalil kattil sinnathil vetri petru nee vaazgha" (In the election of love, with the symbol of bed, may you win and flourish).

[44] Srikanth Srinivasa of the Deccan Herald wrote, "The music by [Rahman], to Vairamuthu's lyrics, sounds good while the movie is on, though whether without the presence of [Rajinikanth] they would have, is another thing.

"[28] K. P. S. of Kalki called the screenplay confusing and dragged, and the film has too many sub plots within short time but praised the performances of Rajinikanth and Ramya Krishnan.

[55] D. S. Ramanujam of The Hindu wrote, "SET TO please and enthral his fans, Arunachala Cine Creations Padaiappa is loaded with scenes and dialogue that will tremendously boost Rajinikanth's image.

Experienced director K. S. Ravikumar goes beyond the accepted limits of cinematic allowances to make the venture of a Bade Appa, so will be the verdict of Rajini's fans" while praising the acting of cast, set design, cinematography, humour and music.

[46] Sify praised Ramya Krishnan's performance but criticised Rajinikanth, stating that he had nothing to do but "be the Superman and spew dialogues".

"[7] Padayappa was a major box office success; according to The Tribune, it was the highest grossing Tamil film at that point.

[51] Nikhil Talreja, an animal activist, criticised one scene from the film which shows a bull charging at Vasundhara who is wearing a red sari.

[60] Talreja also criticised another scene propagating a similarly regressive myth, that snakes drink milk.

Haasan suggested Padayappa be edited in a way that would not disturb the storyline, so Ravikumar and the editor Thanigachalam managed to bring the film down to 14 reels.

[9] When Kumudam's reporter Kannan learnt about the scenes which had been cut, he asked Rajinikanth to release them as Padayappa's sequel.

[65] With the success of Padayappa, Ramya Krishnan, who up to that point in time had only performed glamorous roles,[21] showed her versatility as an actress.

[72] Actress Priyamani, in an interview with Prathibha Joy of The Times of India, stated her character in the Kannada film Ambareesha (2014), is similar to Neelambari.

[73] In Chetan Bhagat's novel, 2 States: The Story of My Marriage (2009), when Krish Malhotra, the protagonist, travels to Nungambakkam by auto rickshaw, the driver stops to worship a poster of Padayappa.

(My way is a unique way);[66] "Poda Aandavane Nammapakkam Irukan’’ (God is on our side);[76] "Adhigama Aasaipadra Aambalaiyum, Adhigama Kobapadra Pombalaiyum, Nalla Vazhndhadha Sarithirame Kidaiyathu" (There is no history of a man who desires too much or a woman who gets too angry living well), "Kashtapadama Edhuvum Kidaikkathu.

[91] Padayappa was also parodied in the Star Vijay comedy series Lollu Sabha, in an episode appropriately named Vadayappa.