Abstract. In order to diagnose internal financial threats to the financial security of domestic corporate enterprises, a three-pronged system of assessment of their financial security has been proposed, in which it is proposed to include a classic financial analysis tool, financial stability assessment toolkit and value management toolkit. Coefficient and discriminant statistical models are used within the classical tools of financial analysis. In order to increase the informativeness of the coefficient model and ensure its comprehensiveness, a matrix for diagnosing internal financial threats to the financial security of a corporate enterprise has been developed, in which the level of financial security is determined by assessing the state of financial performance, grouped into regulatory conformity classes. On the basis of discriminatory statistical models, a model is proposed for assessing the level of financial security of corporate enterprises, depending on the peculiarities of the scale of indicative values of the most popular models of bankruptcy risk diagnosis. To diagnose financial security, a model for assessing the financial stability of operational activities has been proposed as part of the financial stability assessment tool, that measures the level of financial security of corporate enterprises by classifying financial situations according to their degree of stability, depending on the composition and structure of sources of supply requirements for reserve formation. A matrix for diagnosing the internal financial threats to the financial security of a corporate enterprise based on the modified financial reporting model has been developed as a generic tool for measuring financial stability, which allows the determination of the level of financial security by linking indicators of financial stability, solvency and financial risk. Based on the modification of the financial equilibrium matrix, a model has been developed for diagnosing the internal financial threats to the financial security of the enterprise, according to which the level of financial security is determined by the financial soundness zone, depending on the forecasts of the special aggregates. Value-based management (VBM) and balanced scorecard (BSC) are justified to provide an effective strategic management tool with enhanced forecasting capabilities to assess the financial security of corporate enterprises and to propose appropriate tools based on the cascading of financial indicators. Keywords: corporate enterprise, financial security, level of financial security, financial security diagnostic system, financial stability, toolbox, evaluation model, diagnostic matrix. JEL Classіfіcatіon G32, M2 Formulas: 7; fig.: 1; tabl.: 6; bibl.: 21.