The district is named after the town of the same name Tuensang, and the town is named after the village of that which is situated close by the town. It is surrounded on the north by Mon district, on the east by the nation Myanmar, on the south by Zunheboto and Phek district of Nagaland and on the west by Mokokchung district. The latitude of the district is 25º 6`and 27º 4` North and Longitude is 93º 20` and 95º 15` East. The district is situated at an altitude of 1,371.60 meters above sea level; the total area is 4228 sq. km. The main tribes of this district are Changs, Sangtams, Khiamniungans, and Yimchunger. Tuensang is the districts headquarter.

It lies at an altitude of 897.64 sq. km. meters above sea level. It has four sub-divisions; Noklak, Shamatore, Longkhim. The total population of the district is 414801. The density of population is 98 persons per sq. km. and the sex ratio are 913 females per 1000 males. Literacy rate is 51.30 % of the population, and the literacy rate of male to female is 55.97%: 46.12 %. Tuensang was a part of North East Frontier Agency till December 1957, when it was separated from it and joined with Naga Hills to form Naga Hills Tuensang Area in short. Tuensang is the biggest of the eleven districts in Nagaland. The district is oblong in shape and stretches north south.