This paper has solved the task to improve the methodical approach to modeling the integrated index for assessing the level of innovation potential of the European Union countries as a component of the monitoring system. The object of the study is the process of ensuring the innovative development of the European Union; the subject is the model and methods for assessing the level of innovation potential. The relevance of the chosen topic corresponds to the processes associated with innovative development occurring in the world economy and economy of the European Union, as well as the need to evaluate them. Practical activities for integrated assessment of the level of development of innovative potential of countries are considered. Among the methods for assessing the innovation potential, the most widely used are the rating method, integral indices, and sets of indicators. The main disadvantages of the existing methods have been analyzed and outlined, which made it possible to improve the approach that enables to overcome the main problems outlined. An improved methodological approach to assessing the level of innovation potential of the European Union countries consists of a sequence of stages and allows formalizing the process of selecting the components of the integrated index and evaluating the weighting coefficients for these components. The improved methodological approach was tested on data on the innovative development of the countries of the European Union, which made it possible to identify groups of countries according to its level. The methodological approach can improve the analytical support for assessing the level of innovative development, highlight the weaknesses and strengths of the innovation ecosystems of the European Union countries, as well as increase the effectiveness of their innovation policy. The ways to overcome problems in disparities in innovative development between the countries of the European Union, as well as to increase the level of their innovative potential, are considered