Maryanovsky District () is an administrative and municipal district (raion), one of the thirty-two in Omsk Oblast, Russia. It is located in the southwest of the oblast. The area of the district is . Its administrative center is the urban locality (a work settlement) of Maryanovka. Population: 27,595 (2010 Census); The population of Maryanovka accounts for 31.3% of the district's total population.
Maryanovsky district is located in the south of the West Siberian Plain. The Kamyshlov Log runs across the area.