Ust-Kalmansky District (Russian: Усть-Калма́нский райо́н) is an administrative[1] and municipal[4] district (raion), one of the fifty-nine in Altai Krai, Russia.

It is located in the center of the krai.

The area of the district is 2,300 square kilometers (890 sq mi).

[2] Its administrative center is the rural locality (a selo) of Ust-Kalmanka.

[7] The population of Ust-Kalmanka accounts for 41.5% of the district's total population.