The Territoire de Belfort (French pronunciation: [tɛʁitwaʁ də bɛlfɔʁ] ; lit. "Territory of Belfort") is a department in the northeastern French region of Bourgogne-Franche-Comté . In 2020, the population was 140,120. The department, which spans a relatively small surface area of 609.4 km2 (235.3 sq mi), is situated just southwest of the European Collectivity of Alsace . It also shares a border with the Swiss Canton of Jura to the southeast. Its prefecture is Belfort.

The administrative district of Territoire de Belfort was created under the terms of the 1871 Treaty of Frankfurt.