Kozelsky District (Russian: Козе́льский райо́н) is an administrative[1] and municipal[4] district (raion), one of the twenty-four in Kaluga Oblast, Russia.

It is located in the southeast of the oblast.

The area of the district is 1,523 square kilometers (588 sq mi).

[2] Its administrative center is the town of Kozelsk.

[8] The population of Kozelsk accounts for 43.4% of the district's total population.