Kambia District is a district in the Northern Province of Sierra Leone. Its capital and largest city is the town of Kambia. As of the 2015 census, The District had a population of 343,686. Kambia District borders the Republic of Guinea to the north, Port Loko District to the south and Bombali District to the east. The district provides an important Trade route to or from the Sierra Leonean capital Freetown to the Guinean capital Conakry.
The district occupies a total area of 3,108 km2 (1,200 sq mi) and is divided into seven chiefdoms. The district is largely Muslim and its population is ethnically diverse. Most of the Susu people in Sierra Leone live in Kambia District and they form one of the largest ethnic groups in the district.