He is the leader of the Telugu Desam Party and has won twice as an MLA from the Penukonda constituency.
[1] Parthasarathi entered politics by becoming Zilla Parishad chairman of the Anantapur district in 1996.
In 1999, TDP offered him the MP seat of Hindupur and he won with a majority of 134,636,[2] defeating S. Gangadhar of the Congress Party.
In the 2009 election, he contested as an MLA candidate from Penukonda and won[3] in a triangular fight by 14,385 votes, defeating K T Sreedhar of Congress Party.
In the 2014 elections, he again won[4] by defeating Malagundla Sankaranarayana, of YSR Congress Party.