Ust-Ishimsky District (Russian: Усть-Иши́мский райо́н) is an administrative[1] and municipal[4] district (raion), one of the thirty-two in Omsk Oblast, Russia.

The area of the district is 7,846 square kilometers (3,029 sq mi).

[2]} Its administrative center is the rural locality (a selo) of Ust-Ishim,[1] which, as its name indicates,[how?]

is located at the confluence of the Ishim River with the Irtysh.

[3] The Ust'-Ishim man, an ancient skeleton dated to 45,000 years before present, was discovered on the bank of the Irtysh River in Ust-Ishimsky District.