Siddharth Suryanarayan (born 17 April 1979), known mononymously as Siddharth, is an Indian actor who primarily works in Tamil, Telugu, and Hindi language films. Apart from acting, he has also been involved in films as a screenwriter, producer and playback singer. He has also been featured in many advertisements.

After completing his business management studies, Siddharth chose to work in film making and assisted Mani Ratnam, before going on to make an acting debut in S. Shankar's coming-of-age Tamil film Boys (2003). The success of the film provided an opportunity to feature in Mani Ratnam's multi-starrer Aayutha Ezhuthu (2004), before he branched off to receive critical and commercial acclaim in Telugu and Hindi cinema through Nuvvostanante Nenoddantana (2005), Rang De Basanti and Bommarillu (2006). In the late 2000s, he established himself as a bankable lead actor in Telugu films and subsequently chose to become more selective with his projects, while also winning acclaim for his work as a carrom player in Striker (2010) and as a blind warrior in the fantasy film Anaganaga O Dheerudu (2011).

In 2011, he returned to Tamil films after a sabbatical and produced Balaji Mohan's commercially successful romantic comedy Kadhalil Sodhappuvadhu Yeppadi (2012). The actor then had a prolific year in 2014, winning critical acclaim and box office success for his two ventures: Jigarthanda, where he portrayed an aspiring film maker, and Kaaviya Thalaivan, in which he played an actor from the 1920s Madras theater scene. After that, he acted in Sundar C 's horror comedy Aranmanai 2 (2016). Then, he acted in Malayalam film Kammara Sambhavam (2018) written by Murali Gopy. In 2019, he has acted in two Tamil films - Sivappu Manjal Pachai, directed by Sasi, and Aruvam, directed by Sai Shekar.