Kokrajhar district is a district of the Assam state with its administrative headquarters located at Kokrajhar town. Originally, Kokrajhar was a significant part of the undivided Goalpara district. After sometime Kokrajhar was separated from the then Dhubri Sub-division of the Goalpara district and emerged as a Civil Sub-division in 1957. Prior to that, it was only a mere small town with a railway station. Later the place Kokrajhar was promoted into a district on 1st July, 1983. There were four police stations in the district at that time likewise Bijni, Sidli, Kokrajhar and Gossaigaon. Earlier, Bongaigaon was a part of the Kokrajhar district but on 29th September, 1989, Bongaigaon was curved out of the Kokrajhar district and emerged as a separate district. The kingdom of Bhutan is intricately connected with the Kokrajhar district in many significant aspects of life of the people living both in the hills of Bhutan and the plains of Kokrajhar. Since the relation of India is very good with Bhutan hence there is hassle-free movement of the people across the international border for the purpose of business and tours. The Bhutanese town of Gelephu is a nice place to visit from Kokrajhar as it is just across the international boundary.

Bineshwar Brahma, an eminent poet, author and the former president of the Bodo Sahitya Sabha ('Bodo Literary Union') in Assam was born on 28th February, 1948 at Bhatarmari village in the district.

Geographically, the district lies at 26°40'N latitude, 90°27'E longitude and 38 m Altitude. In the year 2021, there was a total 35.46% forest area of total geographical area. The district encompasses a geographical area of 3,296 sq km. and it is bounded by Bhutan on the North, Dhubri district on the South, Bongaigaon district on the East and West Bengal on the West. The climate of the district is characterised as sub-tropical in nature. The actual rainfall in the district was 3105.6 mm in the year of 2021-22.

Administration wise, the district comprises 9 sub-districts, 4 towns and 1,068 villages.

According to 2011 census the district has a population of 8,87,142 out of which 4,52,905 are males and 4,34,237 are females. The district has a sex ratio of 959 (females for every 1000 males) and child ratio of 954 (females per 1000 males). During the year 2001-2011 the population growth rate in the district was 12.04% including 11.18% were males and 12.96% were females. As per 2011 census the major religions in the district are Hindu and Muslim with 59.64% and 28.44% of the total population. The population density in the district is 269 (persons per sq. km.). According to 2011 census the principal languages in the district are Bodo, Bengali and Assamese with 28.39%, 25.40% and 23.78%. In the year 2020 the number of live births in the district was 20,076 out of which 10,932 were males and 9,144 were females. In the same year the number of deaths in the district was 6,576 out of which 4,500 were males and 2,076 were females.

The economy of the district is mainly dependent on agriculture. The adoption of the new agricultural technologies amongst the famers of the district helps to increase the production of various agricultural items. Every year a huge chunk of revenue comes from the agricultural products helps in its economy to a great extent. The district is scantily industrialised since most of the people in the district are engaged in agriculture in order to earn their livelihood. In 2006 the Indian government declared Kokrajhar as one of the country's 250 most backward districts and currently receiving funds from the Backward Regions Grant Fund Programme (BRGF). In the year 2018-19 the gross domestic product in the district was Rs. 8,14,763 lakhs at current price and Rs. 5,93,027 lakhs at constant prices in the year 2011-2012. The net domestic product in the district during the period 2007-08 was Rs. 1,99,578 lakh at current price and Rs. 1,60,275 lakh at constant prices in the year 1999-2000. The Per Capita Income or NDDP, At Factor Cost during the period 2018-19 was Rs. 95,110 at current price and Rs. 71,518 at constant prices in the year 2011-2012.

The district is well known as an abode of several reputed educational institutions. It provides a platform for higher education. Some of its renowned educational institutions are D N Himatsingka High School, The Reality Public School, Kokrajhar Government College, Commerce College, Sangrila School, Bodoland University, Central Institute of Technology, etc. As per 2011 census the literacy rate in the district is 65.22% including 71.89% are males and 58.27% are females. The total number of literates in the district is 4,89,305 including 2,75,220 are males and 2,14,085 are females. The total number of illiterates in the district is 3,97,837 including 1,77,685 are males and 2,20,152 are females.

Upendranath Brahma, popularly known as the "Father of the Bodos" was born on 31st March, 1956 at Boragari village near Dotma in the district. He established himself as the most powerful tribal leader of the twentieth century and belonged to the Bodo tribe. Ranjit Shekhar Mooshahary, a veteran Indian political figure who served as the Governor of the Meghalaya state from 2008 to 2013 was born in 1947 at Odlaguri village in the district.

The district has several centres of attraction which allures many travellers from different parts of the country as well as world. Chakrashila Wildlife Sanctuary, located in the Dhubri and Kokrajhar districts of Assam has the most rarely found golden langur and accepted as the second protected habitat for golden langur in India. The hill of Chakrashila was for the first time declared as a reserve forest in 1966 and on July 14, 1994 it was received the status of sanctuary by the Government of Assam. Some other notable places of interest in the district are Onthai Gwlao, Mahamaya temple, Thandwi Bineswar Brahma Memorial Park, Daimalu Park and many more.