R. Annadurai began his political career in the Democratic Youth Federation of India (DYFI). He was the Madurai District Committee president of DYFI for ten years. He became the secretary of the Madurai (Urban) District Committee of the CPI(M) in 2008. Annadurai has been jailed several times in connection with different agitations.
Annadurai contested the Madurai South constituency in the 2011 Tamil Nadu legislative assembly election, supported by the All India Anna Dravida Munnetra Kazhagam-led coalition. Annadurai won the seat having obtained 83,441 votes (61.92%), defeating the Indian National Congress candidate S. P. Varadarajan.
- "Tamilnadu: Profile of Candidates". Communist Party of India (Marxist). 21 April 2017. Retrieved 2017-04-27.
- "DMK receives drubbing in southern districts". The Hindu. 14 May 2011. Archived from the original on 28 September 2011. Retrieved 27 April 2017.
- "15th Assembly Members". Government of Tamil Nadu. Retrieved 2017-04-26.