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 . Its administrative center is the urban locality (an urban-type settlement) 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.