The purpose of the study is to substantiate the innovation-investment mechanism of the development of economic entities in the conditions of transformational challenges, which involves a recurrent structure for comprehensive consideration of its components. In the researched and substantiated implementation of the recurrent ratio of the innovation-investment mechanism for the development of economic entities in the conditions of transformational challenges, it is possible to take into account: the functions of the innovation-investment mechanism, which include: strategic-target, organizationalmanagement, analytical-informational, social-cultural functions; exogenous and endogenous actors of the mechanism of subjects of economic activity; targeting the achievement of the set tasks of the functioning of the innovation-investment mechanism for the development of economic entities in the conditions of transformational challenges; strategies of innovation and investment development at the level of various levels of government, enterprises and others, taking into account the coherence of the interests of all economic entities; diversification of sources of investment resources; generally accepted methods of the mechanism, which include: planning, forecasting, control, diagnostics, stimulation; specific methods of the mechanism, which include: generation of ideas, compilation, distribution; and management of the innovation and investment mechanism.