Monduli District is one of the seven districts of the Arusha Region of Tanzania. It is located in the northeastern section of the country. It is bordered to the north by Longido District, to the east by Arusha Rural District, to the south by the Manyara Region and to the west by Ngorongoro District and Karatu District. The town of Monduli is the administrative seat of the district. According to the 2002 Tanzania National Census, the population of the Monduli District was 185,237. By 2012, the population of the district was 158,929. The population decreased, as Longido District was split off.