Periyakulam is a major town and a municipality in Theni district, in the Madurai Region, South Indian state of Tamil Nadu. As of 2011, the town had a population of 42,976. Periyakulam is the northern gateway of the district.

Theni District is one of the 38 districts of Tamil Nadu state in India. Well protected by the scenic hill locks, the district is located besides Madurai district. The town of Theni is the district headquarters. The district is divided into two natural divisions: The hilly areas are constituted by parts of the five taluk's Theni, Bodinayakanur, Periyakulam, Uthamapalayam and Andipatti with thick vegetation and perennial streams from the hills on the western side and Cumbum valley which lies in Uthamapalayam taluk. As of 2011, Theni district had a population of 1,245,899 with a sex ratio of 980 females for every 1,000 males.