Gagarinsky District (Russian: Гага́ринский райо́н) is an administrative[1] and municipal[3] district (raion), one of the twenty-five in Smolensk Oblast, Russia.

It is located in the northeast of the oblast.

The area of the district is 2,904.59 square kilometers (1,121.47 sq mi).

[1] Its administrative center is the town of Gagarin.

[6] The population of Gagarin accounts for 64.8% of the district's total population.