Inequality is an inherent property of spatial development, but too high spatial inequality can have a number of serious consequences, from increased fiscal spending aimed at smoothing fiscal space to slowing national economic development and increasing separatist sentiment. The problem of heterogeneity in spatial development is therefore relevant, especially for countries with a large spatial extent, where such inequalities are naturally higher. In Russia the spatial inequality started to grow since the end of the 20th century and is still considered to be high. The aim of the work was to identify the features of the process of polarization of Russia’s spatial development by analyzing the dynamics of economic activity in Russian regions in the 21st century and obtaining extrapolation forecast of interregional distribution of economic activity.The study was carried out with the help of distribution dynamics analysis methods, using the theory of Markov process with discrete time and continuous state space. The above methods have allowed us to: assess the actual distribution of economic activity indicators of the regions and to conclude about its changes in the first two decades of the 21st century; to obtain extrapolation forecast of the distribution of regional economic activity indicators in the long-run, i.e. to forecast long-run spatial equilibrium; to identify and characterize groups of regions forming “convergence groups” in the long-run. The obtained results led to a conclusion about the increasing polarization of Russia’s regions by the level of economic activity both in the study period and in the long run, while maintaining the current trends, to substantiate the need to expand the practice of applying tools of place-based regional policy.