A member of the celebrated theatre group Ninasam, Prashanth Siddi has carved a niche for himself in Kannada cinema ever since his debut in the the Puneeth Rajkumar starrer Paramathma (2011). Over the years, the actor has essayed a number of memorable supporting roles in several films, notable among which are the comedy Bullet Basya (2015), the romantic comedy Prema Geema Jane Do (2016), the romantic action drama Jaguar (2016) and the romantic thriller Beautiful Manasugalu (2017).

In 2018, Prashanth was seen in the movies Bhootayyana Mommaga and A+, the latter of which was directed by Vijay Suryaa and featured Anil Siddhu in the lead role. His 2019 movie credit includes Gara. His 2020 release includes Gentleman.