Ruling AIADMK lawmaker Amman K. Arjunan representing Coimbatore South assembly constituency tested positive for coronavirus, said an official.
He has been admitted to a hospital for treatment. The MLA had been tested 3 days ago.
Earlier, three of his family members had tested positive for coronavirus. The MLA's daughter, son-in-law and granddaughter had been undergoing treatment after testing positive on their return from Madurai recently.
The Health Department took Arjunan's swab samples and found him to be coronavirus positive.
A number of TN lawmakers, from the ruling AIADMK as well as the opposition DMK, have tested positive for coronavirus in recent times. They include DMK MLA J. Anbazhagan, who died after contracting Covid-19.