Sivakarthikeyan attended Campion Anglo Indian Higher Secondary School and then obtained his engineering degree from J.J. College of Engineering and Technology. He then enrolled at IIPM, Chennai and pursued MBA.
While he was studying in college, he participated in various cultural events and performed standup comedy and mimicry on stage. He took three months break from studies and went for auditions of Kalakka Povathu Yaaru, a reality comedy show which is aired on Star Vijay. He ended up winning the show and with that win, he came to limelight. He then became a regular and made his television appearances by participating as a contestant in dance-reality shows, partnering Aishwarya Prabhakar in the famous show Jodi Number One and then in Boys Vs Girls.
Director Pandiraj spotted him while he was hosting the music launch of the movie, Vaagai Sooda Vaa, he immediately approached him to play the title role in his film Marina and he without thinking much signed the project and made his acting debut with the film Marina in 2012. After which he starred in several hit films like Kedi Billa Killadi Ranga, Varuthapadatha Valibar Sangam, and Rajini Murugan amongst others. Currently, he is filming for his next project titled Velaikkaran.
In addition to acting and hosting, he has sung some famous songs like "Royapuram Peter", "I'm So Cool" and "Rajini Murugan" amongst others.