Excessive interregional disparities in the functioning of the socio-economic system in the country substantially affect the dynamics of its socio-economic development, significantly slowing it down, as well as creating obstacles to its efficient and timely structural transformation. The analysis of territorial differentiations of socio-economic development in Ukraine’s regions according to the selected indicators in 2014-2020 shows that despite the general growth of the socio-economic development level in the regions, the asymmetric type of regional development continued to dominate. Excessively high levels of GRP differentiation per capita, capital and foreign direct investment per capita, combined with a slight differentiation of disposable income and local budget revenues (excluding transfers) per capita, showed a significant gap between the efficiency of regional economic systems and quality of inhabitants’ life in the regions. To assess the efficiency of the strategic goals and priorities implementation of the 2020 Regional Development Strategy of Ukraine, an assessment of annual indicators related to the regulation of interregional differentiation is conducted. The negative impact of complex socio-political and financial-economic circumstances, as well as insufficient efficiency of state regional policy instruments, did not allow to achieve the projected rates of most indicators within the priorities of the 2020 Regional Development Strategy of Ukraine related to the regulation of interregional differentiation. The systemic nature of the interregional disparities in Ukraine causes the low efficiency of numerous attempts to solve these problems with the help of separate tools of regional policy. The main focus and resources in the strategic objectives implementation in regional development related to the reduction of interregional disparities should be focused on creating favorable conditions for the most efficient use of regional socio-economic capacity based on the strengths of each region and specialized innovative solutions.