Sathyamangalam (also known as Sathy) is a town and municipality in Erode district in the Indian state of Tamil Nadu. It lies on the banks of river Bhavani, a tributary of Kaveri in the foothills of the Western Ghats. It is about 65 km from Erode and 70 km from Coimbatore. As of 2011, the town had a population of 37,816.