Isilkulsky District (Russian: Исильку́льский райо́н; Kazakh: Есілкөл ауданы, Esilkól aýdany) is an administrative[1] and municipal[3] district (raion), one of the thirty-two in Omsk Oblast, Russia.

The area of the district is 2,800 square kilometers (1,100 sq mi).

[6] Within the framework of administrative divisions, Isilkulsky District is one of the thirty-two in the oblast.

[1] The town of Isilkul serves as its administrative center, despite being incorporated separately as a town of oblast significance—an administrative unit with the status equal to that of the districts.

[1] As a municipal division, the district is incorporated as Isilkulsky Municipal District, with the town of oblast significance of Isilkul being incorporated within it as Isilkul Urban Settlement.