Introduction. Accelerated introduction of modern IC technologies in all areas of the country's social life, development of the digital economy and the national information infrastructure, integration to the global information space and improvement of information security conditions are the strategic objectives of the development of information society in Ukraine. Furthermore, recent years are characterised by active creation of new network organisation forms and cluster cooperation in the IT sphere based on joint endeavours of IT companies, scientific and educational establishments, NGOs and other actors. Organisation of clusters in the IT sphere contributes to not only the optimisation of economic processes management in the course of creation, introduction and use of information technologies and products and services of IT companies, but also to forming of powerful integrated groupings with high economic capacity, which is essential for the development of the national economy.Purpose. The paper aims to analyse both the institutional and investment environment, in which regional IT-clusters develop, in particular the features, tendencies and priorities of their functioning to assess the role of venture capital in the development of the IT sector in Ukraine and to define the strategic directions to improve the instruments of public policy relevant to the development IT clusters in forming of an innovation ecosystem. Methods. Fundamental provisions and principles of innovative development theories and concepts of clustering, economic convergence and integration, diffusion of innovations and place-based innovation systems constitute the methodological basis of the research. Structural-functional and factor analyses are applied in order to reveal major tendencies and preconditions of the development IT sector in Ukraine and to evaluate the impact of venture capital on its establishment and activation. A Multi-factor regression analysis is conducted to perform econometric modeling of the impact of institutional features peculiar to the impact of the entrepreneurship activity environment on the development of the IT sector and forming of its investment capacity in Ukraine. The measures to improve the mechanism to assist the development of IT clusters in forming of an innovation ecosystem are suggested as a result of using the system approach.Results. The authors of the article have elaborated suggestions relating to the improvement of the public IT sector development policy in Ukraine. The intensity of the impact of venture capital on the establishment and development of the IT sector in Ukraine is assessed. The dynamics of exports of Ukrainian IT outsourcing products is researched. It shows that IT outsourcing is one of the most dynamic and leading directions of the IT sector in Ukraine. The evaluation of the impact of entrepreneurship activity and institutional environment on the development of the sphere of information technologies and forming of its investment capacity (the system of venture investment) is conduct...