Kizhinginsky District (Russian: Кижингинский райо́н; Buryat: Хэжэнгын аймаг) is an administrative and municipal district (raion), one of the twenty-one in the Republic of Buryatia, Russia. It is located in the south of the republic. The area of the district is 7,871 square kilometers (3,039 sq mi). Its administrative center is the rural locality (a selo) of Kizhinga. As of the 2010 Census, the total population of the district was 16,509, with the population of Kizhinga accounting for 38.6% of that number.