Thiruvallur Lok Sabha constituency is a newly formed Lok Sabha (Parliament of India) constituency after the 2008 delimitation. Its Tamil Nadu Parliamentary Constituency number is 1 of 39. It was formed after merging the assembly segments of Gummidipoondi, Ponneri (SC), Tiruvallur, and Poonamallee (SC), Madhavaram, which were earlier parts of Sriperumbudur constituency and the newly formed Avadi.
The constituency had previously existed for three elections from 1951 to 1962.
It is reserved for Scheduled Castes (SC).