Modern economic development, globalization and the process of purposeful management of economic activities are associated with predicting the consequences of the implementation of management decisions by modeling a controlled process. Effective financial management of enterprises directly determines its sustainable functioning and development. A variety of financial instruments are used in corporate finance management. Leverage is a specific financial instrument, the economic nature of which is not sufficiently researched and is ambiguous for practical application. A prerequisite for financial policy is to maintain profitability at a level consistent with the cost of capital and financial risk. This circumstance determines the possibility and rationality of using the financial leverage mechanism in the practice of financial management of companies, since it is it that allows us to trace the relationship between profitability indicators and the structure of funding sources. The formation of the optimal structure of the capital of enterprises is a strategic priority of the theory of corporate finance. In this regard, most scientific works consider leverage as an activity tool that characterizes the use of borrowed funds by companies. In general terms, leverage can be represented as a process of managing the assets and liabilities of an enterprise aimed at increasing profits. This is a certain factor, a small change in which can lead to a significant change in effective indicators, give the so-called leverage effect. In this regard, the work investigates the main variables affecting the size and structure of sources of capital formation of an enterprise, such as: industry, size, age and growth prospects of the enterprise, profitability and liquidity of assets, the impact of business and foreign exchange risk, interest coverage ratio, share of tangible assets, collateral value of assets or tangibility of assets. Considered the modern concepts of leverage and its place in the financial management of companies, as a self-regulating system, is specified. The proposed financial mechanism of financial management based on financial leverage. Thus, the use of financial leverage in management can bring significant economic benefits. Planning a long-term level of development, areas of activity, capital structure, resources and other indicators using leverage will allow an enterprise to be much more likely to realize its goals, reduce risks, and ensure its growth and business continuity. Moreover, leverage allows you to optimize the capital structure according to the criterion of maximizing the level of projected profitability.