Tuensang District is the largest and the eastern most district of Nagaland, a state in North-East India. Its headquarters is Tuensang.

Tuensang is one of the original three districts, along with Mokokchung district and Kohima district formed at the time the state was created. Over the decades, the district has gradually diminished in size with the carving out of Mon, Longleng and Kiphire districts from it.

The district shares a long and porous international border with Myanmar all along its eastern sector. It is bounded by Mon in the north east, Longleng in the North, Mokokchung and Zunheboto in the West and Kiphire in the South. Nagaland’s highest peak, Mount Saramati (3840 metres) is located in this district. Dikhu and Tizu are the main rivers of the district.

In 2006 the Ministry of Panchayati Raj named Tuensang one of the country’s 250 most backward districts (out of a total of 640).It is one of the three districts in Nagaland currently receiving funds from the Backward Regions Grant Fund Programme (BRGF).

According to the 2011 census Tuensang district has a population of 196,801, roughly equal to the nation of Samoa.This gives it a ranking of 590th in India (out of a total of 640).Tuensang has a sex ratio of 930 females for every 1000 males, and a literacy rate of 73.7%.

Changs, Sangtams, Yimchunger and Khiamniungans are the main indigenous tribes of this district. Besides, Aos and Semas form a small part of the district’s population. Christianity is the main religion though animistic beliefs are still practised by a small minority specially along the Myanmar border.