Ustyansky District (Russian: Устьянский райо́н) is an administrative district (raion), one of the twenty-one in Arkhangelsk Oblast, Russia. As a municipal division, it is incorporated as Ustyansky Municipal District. It is located in the south of the oblast and borders with Verkhnetoyemsky District in the northeast, Krasnoborsky and Kotlassky Districts in the east, Velikoustyugsky, Nyuksensky, Tarnogsky, and Verkhovazhsky Districts, all of Vologda Oblast, in the south, Velsky District in the west, and with Shenkursky District in the northwest. The area of the district is 10,700 square kilometers (4,100 sq mi). Its administrative center is the urban locality (an urban-type settlement) of Oktyabrsky. Population: 30,581 (2010 Census); 37,131 (2002 Census); 45,352 (1989 Census).