The subject of the research in the article is the main tendencies of investment and innovation activity of business entities. The purpose of the work is to determine the main tendencies of investment and innovation activity of economic entities at the international, macro and microeconomic levels in the conditions of European integration with application of methods of economical and mathematical modeling. Task: definition of integral indicator of investment and innovation activity of economic entities at international, macro and microeconomic levels. To achieve the goal, the following methods were used: abstract-logical method, method of analysis and synthesis, logical-content analysis - formation and substantiation of the system of indicators of evaluation of investment and innovation activity of subjects of management; generalization and abstracting - the study of categorical apparatus of investment and innovation activity of business entities, multidimensional factor analysis - for the classification and systematization of the space of signs of research and the grouping of factors by their economic content. The following results are obtained: to increase the objectivity and reliability of the analysis, the corresponding integral indicators characterizing each level are combined into a generalized integral index of investment and innovation activity of economic entities, calculated by the method of additive convolution, taking into account the coefficients of significance of each level. Significance is determined on the basis of the use of expert survey method taking into account the predominance: for foreign investments and for domestic investments. Conclusions: the theoretical and methodical approach to the definition of investment and innovation activity of economic entities is proposed, which provides the opportunity to determine the most influential factors on the level of investment-innovation activity economic entities at the international, macro- and microeconomic levels in the context of European integration and provides an integrated valuations taking into account the predominance of foreign or domestic investment, which contributes to the adoption of sound management decisions.