[2] He made his acting debut in 2010 with the film Sindhu Samaveli and gained recognition for his roles in Poriyaalan (2014), Vil Ambu (2016) , Pyaar Prema Kaadhal (2018) and Parking (2023).
[18][19][20] After half a dozen films, he was noticed for his performance in the thriller Poriyaalan (2014), where he portrayed a young civil engineer aspiring to become a property developer caught up in a real estate scam.
[21][22] The success of Poriyaalan prompted film maker Suseenthiran to select Harish to portray a leading role in his production, Vil Ambu (2016).
[23] Appearing in an ensemble cast including his own father Kalyan, Sri and Chandini Tamilarasan, critics praised Harish's performance stating he "scores big time" and "is bound to be noticed for his charming looks and clean features".
[34] Following his successful appearance on the show, Harish Kalyan was signed on to play the lead role in Elan's romantic comedy Pyaar Prema Kaadhal (2018), which featured him opposite fellow Bigg Boss contestant Raiza Wilson.
[38][39] In 2019, Harish Kalyan starred as a middle-class boy with major anger issues and a troubled childhood in Ispade Rajavum Idhaya Raniyum directed by Ranjit Jayakodi.
[40][41] Critic from The Times of India found that "Harish Kalyan excels as the aggressive and possessive youngster, a character which is quite contrasting to the one he essayed in Pyaar Prema Kaadhal”.
[51] He was also roped in to play one of the lead in Chimbu Deven's interesting entertainer titled Kasada Thapara (2021) which is produced by Venkat Prabhu's Black Ticket Company.