Shemurshinsky District (Russian: Шемурши́нский район; Chuvash: Шăмăршă районӗ) is an administrative and municipal district (raion), one of the twenty-one in the Chuvash Republic, Russia. It is located in the south and southwest of the republic. The area of the district is 799.1 square kilometers (308.5 sq mi). Its administrative center is the rural locality (a selo) of Shemursha. Population: 14,759 (2010 Census); 16,588 (2002 Census); 18,186 (1989 Census). The population of Shemursha accounts for 25.5% of the district's total population.