Vridhachalam is a legislative assembly constituency in Cuddalore district in the Indian state of Tamil Nadu. Before the 2008 delimitation, it was part of Chidambaram Lok Sabha constituency. Since 2008, it has been a part of Cuddalore Lok Sabha constituency. This constituency was won by popular actor Vijaykanth, during the 2006 Assembly election, under his new party Desiya Murpokku Dravida Kazhagam. It is one of the 234 State Legislative Assembly Constituencies in Tamil Nadu.