The demographic crisis in Ukraine at the beginning of the 21st century was associated with a decrease in the birth rate in the period 1991-2000. Subsequently, this caused a significant reduction in the number of labor resources and an increase in the number of the retirement age population. Halting the decline in birth rates after 2000 did not improve the situation. According to the forecast based on the model of demographic changes, the total population of Ukraine had a tendency to decrease by almost 37% until 2045. Russian aggression in 2014 led to the occupation of the territories of Ukraine, namely the annexation of Crimea and the capture of parts of the Donetsk and Luhansk regions. This caused a mass migration of the population to the territory controlled by Ukraine during the occupation. But part of the population remained in the occupied territory. A military invasion in February 2022 further worsened the demographic situation. It is still impossible to fully determine the consequences of the war, but it is already possible to classify the trends of such changes