| En Name: | Sernursky District |
| Ru Name: | Сернурский район |
| Loc Name1: | Шернур кундем |
| Loc Lang1: | Meadow Mari |
| Loc Lang2: | Hill Mari |
| Coordinates: | 57.092°N 48.966°W |
| Image Coa: | Coat of arms of Sernursky District.svg |
| Federal Subject: | Mari El Republic |
| Adm Data As Of: | October 2014 |
| Adm Ctr Type: | urban-type settlement |
| Adm Ctr Name: | Sernur |
| Urban-Type Settlement Of District Significance Type: | Urban-type settlements |
| No Of Urban-Type Settlements Of District Significance: | 1 |
| Selsoviet Type1: | Rural okrugs |
| No Of Selsoviets Type1: | 8 |
| No Of Urban-Type Settlements: | 1 |
| No Of Rural Localities: | 145 |
| Mun Data As Of: | August 2014 |
| Mun Formation1: | Sernursky Municipal District |
| Mun Formation1 No Of Urban Settlements: | 1 |
| Mun Formation1 No Of Rural Settlements: | 8 |
| Area Km2: | 1032 |
| Pop 2010Census: | 25672 |
| Urban Pop 2010Census: | 33.8% |
| Rural Pop 2010Census: | 66.2% |
| Website: | http://mari-el.gov.ru/sernur |
| Date: | October 2012 |
| Population of Sernursky District | |
| Label1: | 2010 Census |
| Data1: | 25,672 |
| Label2: | 2002 Census |
| Data2: | 25,280 |
| Label3: | 1989 Census |
| Data3: | 27,263 |
| Label4: | 1979 Census |
| Data4: | 28,883 |
Sernursky District (Russian: Се́рнурский райо́н; Шернур кундем, Šernur kundem) is an administrative[1] and municipal[2] district (raion), one of the fourteen in the Mari El Republic, Russia. It is located in the northeast of the republic. The area of the district is 1032km2. Its administrative center is the urban locality (an urban-type settlement) of Sernur.[3] As of the 2010 Census, the total population of the district was 25,672, with the population of Sernur accounting for 33.8% of that number.
Within the framework of administrative divisions, Sernursky District is one of the fourteen in the republic. It is divided into 1 urban-type settlement (an administrative division with the administrative center in the urban-type settlement (inhabited locality) of Sernur) and 8 rural okrugs, all of which comprise 145 rural localities. As a municipal division, the district is incorporated as Sernursky Municipal District. Sernur Urban-Type Settlement is incorporated into an urban settlement, and the eight rural okrugs are incorporated into eight rural settlements within the municipal district. The urban-type settlement of Sernur serves as the administrative center of both the administrative and municipal district.