Abstract: Throughout the XX century, the demographic policy of the Soviet State was aimed mostly at working-age population or labor resources, taking into account regional and territorial aspects. Demographic change of the early XXI century was the result of political events of the 1990s, when the concept of population policy was under the radar of the government. The socioeconomic cataclysms destabilized the employment structure of population, caused deterioration of living standards, which affected the demographic characteristics of the XXI century. The demographic policy crisis of the late XX century generated one of the crucial organizational issues faced by the northern regions. This article is dedicated to the main demographic trends in the northern regions of Buryatia, which were affected by the construction of the Baikal-Amur Mainline, since completion of the construction project until stabilization of socioeconomic situation in the country by the early 2010s. In the course of construction of the Baikal-Amur Mainline, Buryatia took the lead in terms of birth rate, and ranked last in mortality index per thousand people. This testified to relative density of young poplar and children in the age structure, as well as stable population reproduction with insignificant demographic fluctuations.