Mongun-Tayginsky District (Russian: Монгу́н-Тайги́нский кожуун; Tuvan: Мөңгүн-Тайга кожуун, Möñgün-Tayga kojuun) is an administrative and municipal district (raion, or kozhuun), one of the seventeen in the Tuva Republic, Russia. It is located in the southwest of the republic. Its administrative center is the rural locality (a selo) of Mugur-Aksy. Population: 5,661 (2010 Russian census); 5,938 (2002 Census); 5,576 (1989 Soviet census). The population of Mugur-Aksy accounts for 73.4% of the district's total population.