Central Asia is the only macro-region of the post-Soviet space where population growth has been observed over the past three decades, accompanied by a significant restructuring of the ethnic structure. The purpose of the study is to identify the most significant factors that influenced the change in the national composition of the population of the countries of Central Asia that occurred in the post-Soviet era, or more precisely, in the period between 1989 and 2021. The study is based on statistical, graphical and cartographic methods. The analysis showed that the most important factor influencing the change in the ethnic structure of the population of Central Asia in the post-Soviet period was the high natural increase in the titular peoples of the countries of the macroregion, which led to a more than doubling of their numbers in their republics. The second important factor in the ethnic restructuring of the Central Asian states was the reduction in the size of the non-titular population of the republics as a result of their migration outflow and natural decline. The opposite dynamics of the titular and non-titular populations of the Central Asian republics in the post-Soviet period led to a sharp increase in the share of titular peoples in their populations. Currently, in all countries of Central Asia, the share of titular peoples exceeds 70 %, and Tajikistan can already be considered a mononational state.