|Time zone||IST (UTC+5:30)|
|Vehicle registration||TN 36|
Sathyamangalam (also known as Sathy) is a small city in Erode district in the Indian state of Tamil Nadu. It lies on the banks of Bhavani River, a tributary of the Kaveri in the foothills of the Western Ghats. It is about 65 km from Erode and 70 km from Coimbatore.
Sathyamangalam is situated on the southern side of the Western Ghats, which extends towards the east from the Nilgiri mountains. The town lies close to the border of the adjoining Karnataka State. The nearby Bhavanisagar Dam, a picnic spot, and Bannari Amman Temple, a centre of pilgrimage, both attract people and tourists all the year round. There is also a heavy movement of people to Karnataka State, especially to Mysore and Kollegal, through this town.
The town is situated at a distance of 65 km from district headquarters Erode, connected through State Highway 15 via Gobichettipalayam. The Coimbatore-Bangalore National Highway (NH 209) passes through this town. The nearest Railway Station is Mettupalayam in Coimbatore District, at a distance of 43 km and Erode Railway Junction. The town is also linked with Bhavani Sagar, Mettupalayam and Bhavani Town with District roads, and links the towns of Chamarajanagar and Mysore in neighbouring Karnataka State, through Highways. The nearest airport is located at Coimbatore, 68 km, away.
The general topography of this town is not flat and the town is generally covered by the sloping lands with steadily lying land in the North towards ghat stretches. The river Bhavani flows at the center of the town from west to east. Agricultural wet lands are predominant on both sides of the river. The dry lands are predominant in the northern side of the town. The weekly market at Sathyamangalam serves the rural people. Sathyamangalam is a medium-sized town with an agricultural linter land on all sides. It is one of the Taluk headquarters in Erode District and also an urban center located near the state boundaries of Tamil Nadu and Karnataka. It is one of the very old settlements of Tamil Nadu. The town has developed on both sides of Bhavani River and along the highways. The rate of urban growth of Sathyamangalam is very low, because the Northern side of this Municipality is surrounded by reserved forests. Poor industrial activities are also one of the reasons for slow growth rate of urban development. Sathyamangalam Municipality's area in 29.24 km, comprising four revenue villages. Only 10.46% of the municipal area is developed as urban area and the remaining 89.54% remains undeveloped agricultural land. Much land is available for development, but the opportunity for development in the near future is slight due to financial weakness among the public.
Sathyamangalam is also the name of a Reserve Forest under the Wildlife Protection Act, 1973. It is contiguous with the Biligirirangan Temple Wildlife Sanctuary to the north in neighbouring Chamarajanagar District of Karnataka, and together forms a vital corridor for faunal movements, mainly elephants. The forests were also the home of the cold-blooded Indian bandit Koose Muniswamy Veerapan, who made a living exploiting ivory and sandalwood from the forests and selling them on the black market. A major National highway NH 209 connecting Coimbatore to Bangalore via Sathyamangalam passes through the forests.
As of the census of India 2001, Sathyamangalam had a population of 33,722 comprising 17,124 males and 16,598 females, making the sex ratio (number of females per thousand males) of the town to 969. A total of 3,299 people were under six years of age and the child sex ratio (number of females per thousand males under six years of age) stood at 938. The town had an average literacy of 74.6%, higher than the national average of 59.5%. A total of 2,947 comprising 9.69% of the population belonged to Scheduled Castes (SC) and 121 comprising 0.4% of the population belonged to Scheduled tribes (ST). There were are total of 8,804 households in the town. As of 2001, Sathyamangalam had a total of 12,534 main workers: 929 cultivators, 1,548 agricultural labourers, 869 in house hold industries and 9,188 other workers. There was a total of 2,072 marginal workers: 30 marginal cultivators, 213 marginal agricultural labourers, 147 marginal workers in household industries and 1,682 other marginal workers.
Sathyamangalam is a class-III town and also the headquarters for Sathyamangalam Taluk in Erode District. The town was upgraded as a third grade Municipality from the status of Town Panchayat on 17.1.1970, as per G.O.Ms.No. 58 RDLS Dept. dated 12.1.70, and subsequently raised as a second grade Municipality on 1.4.77 as per G.O.Ms.No. 642 RDLA Dept. dated 15.4.77. It functions as a First Grade Municipality as per G.O.Ms.No. 855, MAWS Dept., Dated 22.5.98. The population, according to the 2001 census, is 33,748.
The nearest railway station is Erode Junction (63 km). The Erode-Chamrajnagar railway line scheme was proposed in 1915 via Gobichettipalayam, Sathyamangalam. The British conducted surveys in 1922, 1936 and 1942 and survey stones were also laid for the proposed railway line. But after Independence the scheme did not take off and was rejected later amid concerns about destruction of forests and wildlife.
The nearest airport is Coimbatore International Airport, which is 65 km by road, which has regular flights from New Delhi, Kolkata, Mumbai, Ahmedabad, Bangalore, Kozhikode, Chennai, Hyderabad, Pune, Sharjah and Singapore.
Sathyamanagalam assembly constituency was merged with Bhavani Sagar as a part of delimitation by the Election Commission of India. It was a part of the Gobichettipalayam parliamentary constituency until 2010 before being merged with Nilgiris. 
- "General information". Sathyamangalam Municipality. 2011. Retrieved 2013-08-08.
- "Sathyamangalam forests declared as sanctuary". Chennai, India: The Hindu. 2008-12-24. Retrieved 2009-04-14.
- "Primary census abstract 2001". Directorate of Census Operations – Tamil Nadu. 2001. Retrieved 2012-12-29.
- "About Municipality". Sathyamangalam Municipality. 2011. Retrieved 2013-08-08.
- "About Sathyamangalam". Sathyamangalam Municipality. 2011. Retrieved 2013-08-08.
- "List of Parliamentary and Assembly Constituencies" (PDF). Tamil Nadu. Election Commission of India. Retrieved 2008-10-10.