Theni is a city and district in western part of Tamil Nadu state in South India. Theni District is home to Theni, Bodinayakanur, Cumbum, Kudalore, Chinnamanur, and several other small villages. Its economy is mostly agricultural. It is bounded on the north by Dindigul District, on the east by Madurai District, on the southwest by Virudhunagar District, and on the west by Kerala state.

Theni is the newly formed District surrounded byWestern ghats. The main occupation of the inhabitants is agriculture.Periyar Water flows along with the Mullai river through this district and it finally reaches the Dam called Vaigai.