Devin Municipality is situated in the southwestern part of the Rodopi mountain along the river Vache and borders with the municipalities of Smolyan, Borino, Batak, Krichim, Perushtitsa and Chepelare, and to the south with the Hellenic Republic. Devin municipality is one of the ten constituent municipalities of Smolyan region and has an area of ​​575 sq. Km. It occupies the northwestern part of the Smolyan region.

The municipal center of Devin is situated in Devin Mountain at 710 meters above sea level, in a small valley about 2 km west of the merger of Devin River and Vacha River. It is surrounded to the south by the Devinska mountain, to the northwest from the peak of Grebenets and to the east by the slopes of Chernatitsa. It is 45 km. northwest of Smolyan and 220 km. from Sofia.

The population of Devin municipality as of 31.12.2017 is 13,009 people, of which 7,023 live in the municipal center of Devin. The municipality consists of 16 settlements - one town and 15 villages - Biden village, Breze village, Vodeni padd, Grohotno village, Gyovren village, Jrebovo village, Kesten village, Lyaskovo village, Mihalkovo village , Osikovo village, village of Celcha, village of Stomanovo, village of Teshel, village of Trigrad, village of Churekovo.

The relief of the municipality is mountainous, with steep and inaccessible slopes and deep valleys, sloping to steep ridges. The climate is transcontinental and is characterized by lower summer temperatures and heavy rainfall. The municipality is rich in water resources: karst springs, rivers, dams, as well as hot mineral springs with water temperatures from 16º to 76ºC in the "Bedenski bani" locality near the village of Breze, in the town of Devin (water with very good table top quality ), Mihalkovo village (natural carbonated water - table and treatment), Pozestra site and Nistan district.