The district was created on 14 November 1987, when it was split from Tirap district.
Geography
Changlang district occupies an area of, comparatively equivalent to Indonesia's Lombok Island. It falls in a region that receives high rainfall. The region is rich in wildlife with a different kind of flora and fauna. The district has both plains and highlands. Most of the plains are in the valley of Dihing. The area is prone to occasional floods.
The Dihing is the main source of fishes for the local people. The freshwater fishes are very much in demand they hardly reach major towns nearby like Tinsukia, Doomdooma, Digboi and Dibrugarh.
Administrative divisions
There are 5 Arunachal Pradesh Legislative Assembly constituencies located in this district: Bordumsa, Miao, Nampong, Changlang South and Changlang North. All of these are part of Arunachal East Lok Sabha constituency. The Changlang district has five Sub-Divisions namely Changlang, Manmao, Jairampur, Bordumsa, and Miao. Changlang Sub-Divisions covers four circles, namely Changlang, Khimiyang, Namtok and Yatdam. Manmao Sub-Division covers three Circles, namely Manmao, Renuk, and Lyngok-Longtoi. Jairampur Sub-Division covers three Circles, namely Nampong, Jairampur and Rima-Putak. Bordumsa Sub-Division has got only two circles Bordumsa and Diyun. And Miao Sub-Division covers three circles namely Miao, Kharsang and Vijoynagar. Total, there are fifteen Circles, five Blocks, and five Subdivisions in Changlang district. There are two municipalities Changlang and Jairampur. The administrative setup is based on single-line administration which aims to keep close co-operation amongst various developmental departments with the district administration and thus, to work together for the speedy development of the area. The district has four Sub-Divisions and a total of 12 circles as shown in Table 2.1 below. The Deputy Commissioner is the overall in-charge of the district administration maintains law and order with the help of administrative officers and police forces. Moreover, the villagers have their own customary administrative systems in the form of traditional village councils consisting of the Gaon Buras and members.
Transport
There is no good road transport in the region. The people are commuting on the roads that Oil India Limited build some decades back. The proposed Mago-Thingbu to VijaynagarArunachal Pradesh Frontier Highway along the McMahon Line, and will pass through this district, alignment map of which can be seen and .
The Namdapha Tiger reserve is located in Miao town of this district.
Health services
Although the region is one of the most populous in Arunachal Pradesh, there are hardly any hospitals. It is a great challenge to travel to good hospitals in Assam.