Implementation of the policy of attracting investments into state and communal infrastructure requires the study of the mechanism of implementation of investment projects on mutually beneficial terms for business, state and community. The theory and practice of application of the institute of public-private partnership (here in after PPP) are described in the course of implementation of investment projects aimed at innovative development and ensuring economic security of the state. It is determined that PPP projects are implemented on the basis of project financing, the mechanism of which in the world practice allows to attract business funds, various financial and credit structures for the implementation of investment projects on the basis of long-term financing, guarantees, responsibility, redistribution of risks, etc. It was established that on the PPP conditions the state receives a functioning object, saving on state budget financing of its construction or reconstruction, and entrepreneurs, in turn, earn money for its further exploitation. Determining the synergistic effect of the project implementation within the framework of the PPP will optimize the state's efforts to achieve the goal of increasing the welfare of the population. The essence of public-private partnership is revealed and its role in the modern economy is identified. The socio-economic assessment of the heat supply modernization project in the city of Malyn, Zhytomyr region, within the framework of the PPP, was carried out on the basis of the objectives of public-private partnership, compliance with the priorities of state and city development, as well as the economic, social, legal and environmental aspects of the PPP project. The feasibility of implementing this project has been proven by key indicators of the analysis of the effectiveness of public-private partnership implementation

Keywords: state energy security, energy saving technologies, public-private partnership, principles of public-private partnership, PPP management system, investment project, discounting, efficiency, environmental assessment, synergy effect