Sathyamangalam is a town and municipality in Erode district in the Indian state of Tamil Nadu. It lies on the banks of the Bhavani River, a tributary of the Kaveri straddling the Eastern and Western Ghats. It is the headquarters of Sathyamangalam taluk. It is located about 65 km (40 mi) from the district headquarters Erode. As of 2011, the town had a population of 37,816.