Chamzinsky District (Russian: Чамзинский райо́н; Erzya: Чаунзабуе; Moksha: Чамзинкань аймак) is an administrative and municipal district (raion), one of the twenty-two in the Republic of Mordovia, Russia. It is located in the east of the republic. The area of the district is 1,009.5 square kilometers (389.8 sq mi). Its administrative center is the urban locality (a work settlement) of Chamzinka. As of the 2010 Census, the total population of the district was 31,639, with the population of Chamzinka accounting for 29.9% of that number.