Severo-Baykalsky District is an administrative and municipal district (raion), one of the twenty-one in the Republic of Buryatia, Russia. It is located in the northeast of the republic. The area of the district is 54,000 square kilometers (21,000 sq mi). Its administrative center is the urban locality of Nizhneangarsk. As of the 2010 Census, the total population of the district was 14,035, with the population of Nizhneangarsk accounting for 35.8% of that number.