Siddharth Suryanarayan popularly known as Siddharth or Siddhartha, born 17 April 1979, Mother Tongue - Tamil) is an Indian movie actor from Tamil Nadu who has appeared in Tamil, Telugu and Hindi films..

He studied in the D.A.V School, Gopalapuram, Chennai and at Sardar Patel Vidyalaya, Delhi. He got his B.Com (Honors) degree from Kirori Mal College, New Delhi. Siddharth was popularly known as "Sidy" in school and college, and was part of the reputed theatre group of the college The Players. He was also president of the college's debating society and attended the World Debating Championships. He completed his MBA atS.P Jain Institute of Management & Research, Mumbai. He was declared "CNBC MANAGER OF THE YEAR" in 1999.

Siddhu started in films as an assistant director to Mani Ratnam, for the critically acclaimed Tamil film Kannathil Muthamittal. His first role was in Boys as "Munna", directed by S. Shankar. His mentor Mani Ratnam then offered him a role in the Tamil film Aayitha Ezhuthu. His first solo lead role was the role of Santosh in the Telugu film Nuvvostanante Nenoddantana (2005) opposite Trisha Krishnan, which was commercially successful. In 2006, he was chosen to play "Karan", one of the protagonists in the Hindi movie Rang De Basanti, which released in January 2006 . He then scripted a Telugu film "Chukkallo Chandrudu" which was received well by critics. He followed this with "Bommarillu" in Telugu which is among the highest grossing Telugu films of all time. He has worked with director Vishal Bhardwaj and Oscar winning Lensman Guillermo Navarro on a short film titled "Blood Brothers" which screened at the Toronto film festival. He is currently working on his second Hindi film titled "Striker" directed by Chandan Arora.