Tanjung Selor is a district in Bulungan Regency, North Kalimantan Province of Indonesia, and the administrative capital of the province, as well as the capital of Bulungan Regency. The district has an area of 1,277.81 km² and a population of 39,439 at the 2010 Census. The district is served by the Tanjung Harapan Airport.