Subject of this article investigation is theoretical and methodological aspects of institutional support of international economic cooperation in the sphere of renewable energy. Objective of the article is to highlight the core and do research into the common factors and newest trends concerning institutional support of international economic cooperation in the sphere of renewable energy. Method. When in use for article preparation the following general scientific research methods were used: historical and logical methods are applied while investigating into international experience and analysis of international economic cooperation evolution in energy area; abstract and specific methods as well as methods of analysis and synthesis are used for justification of priorities, rules and goals of institutional support of international economic cooperation in the sphere of renewable energy and definition of international organizations role while their implementing. Causal (cause-and-effect) method of scientific research is employed to determine priorities and challenges regarding institutional support of international economic cooperation in the sphere of renewable energy development as an essential part of the sustainable development transition processes. Results. The development of renewable energy in XXI century has become a strategic priority of world energy market modernization, promotes the solution to the problem of global warming, reduces the risks of CO2 emissions as well as related risks of increase in climate refugees, world countries’ coastal areas flooding, so reduces a risk of famine and incidence of poverty among the Earth population. Institutional support of renewable energy development is provided by such international organizations as UN, UNDP, UNEP, URS, BASE, UNIDO, IRENA etc. UN Framework Convention on Climate Change (UNFCCC), Kyoto Protocol (expired), Paris Agreement on Climate Change were adopted. According to UNDP forecasts, scenarios for the share of renewables in world supplies by 2050 in balance of fuels and electric power ranges widely from just 27 percent to 54 percent and will rank the leading positions among other sources of energy resources on the Earth. Among the priorities of international economic cooperation in the sphere of renewable energy there are the following: providing institutional support of renewable energy production growth, development and introduction of ‘green tariffs’, benefits and economic stimuli as well as principles of energy efficiency and energy-saving. Institutional support of energy infrastructure development, transportation and transit, conservation and rational use of renewable energy resources is of great importance. Range of results application. International economic affairs and world economy. Conclusions. Among the main priorities of institutional support of international economic cooperation in the sphere of renewable energy development the following ones should be mentioned: organization of international consultations on framework development in the sphere of renewable energy promoting and use; drawing-up the rules and principles of safety and rational energy consumption; promoting technology and knowledge transfer development in the sphere of renewable energy; establishment of regional R&D centers as well as centers of experience exchange in the sphere of renewable energy development; distribution of successful world experience in the sphere of renewable energy use; planning of financial provision of the program on renewable sources of energy use; compilation of statistical data in the sphere of renewable energy development; monitoring and adjustment of strategies on renewable energy development. Transition to global renewable energy use is an essential part of a process of sustainable development in the XXI century.