Thirunageswaram is a panchayat town in Thanjavur district in the Indian state of Tamil Nadu.

Thirunageswaram is one of the many temple towns in the state which is named after the grooves, clusters or forests dominated by a particular variety of a tree or shrub and the same variety of tree or shrub sheltering the presiding deity.

The town receives a rainfall every year (120 cm) and is known for its extremely fertile land and chief crops include Rice and Corn.

An important feature of Naganatha Swami temple is that of Rahu bhagawan (one of the nine celestial bodies) sannathi.

At this time, the milk that is poured on the statue turns blue when it passes over the body and once again to white after it reaches the floor.

The mythological serpents Aadi Seshan, Dakshan and Kaarkotakan worshipped Shiva here.