The Eurasian Economic Union (EAEU) system of the economic security is required to form the path of efficient development of the Common Economic Space (CES). The aim of the study is to quantify economic security and develop measures to ensure macroeconomic stability of the EAEU member states. The index estimation method, cross-country comparisons of indicators, and the expert ranking method were selected for research. The authors' method of calculating the integral index of economic security of an integration association has been presented, which includes three groups of indicators: development of the national economy, social and financial security. The results of the analysis have revealed that the highest level of economic security has been established in the Russian Federation and the Republic of Belarus. However, low GDP per capita in all EAEU countries, as well as low rates of GDP growth, production, industrial production, and value added in agriculture and gross capital formation in the largest EAEU member state -the Russian Federation, and a large volume of foreign currency borrowings in Belarus and Kyrgyzstan affect the level of economic security of the integration association. The most important threats to economic security have been identified as a result of expert ranking: tougher sanctions, depreciation of national currencies, and spontaneous migration processes. The results of the study allow the authors to conclude that measures must be developed to coordinate monetary policies, as well as to expand integration in the social and labor spheres.