Gautham Karthik is a Tamil film actor was born to Tamil film actor Karthik Muthuraman and actress Ragini Karthik. He is the grandson of actor R. Muthuraman. He went to a boarding high school, Hebron School at Ooty. He spent his growing years in Udhagamandalam and was graduating at Christ University, Bangalore, until film maker Mani Ratnam approached him for his debut film Kadal. He didn't watch a lot of Tamil cinema since he spent his childhood in a boarding school. Before that, Gautham was not connected with the film industry. In college he performed as a guitarist and vocalist in his band 'Dead End Street'. He has two younger siblings, Ghayn Karthik and Thiran Karthik.
In Gautham's film debut, Kadal, the female protagonist is Thulasi Nair. In his father's film debut, Azhaigal Oivathillai, the female protagonist is Thulasi Nair's mother, Radha.
In college he performed as a guitarist and vocalist in his band 'Dead End Street'.
He admitted that he didn't know much of Tamil cinema due to studying in Hebron School, which is a co-educational day and boarding independent international Christian school in Ootacamund.