The article reveals the basic theoretical approaches to the formation of a green urban ecosystem in the conditions of modern urbanization. The importance of ecological planning in cities and the impact of green spaces on improving the urban environment are substantiated. The necessity of introducing new methods of managing urban ecosystems, taking into account modern environmental challenges, has been established. Based on the set goal, modern approaches to planning and management of green infrastructure are considered. It is argued that the integration of natural components into urban structures is a key prerequisite for the sustainable development of urban areas. The main principles of creation and maintenance of the urban ecosystem were studied, in particular in the context of adaptation to climate change. The main trends in the development of green spaces in cities have been determined. Further perspectives of research should be directed to the integration of innovative solutions to improve the ecological condition of urban areas. The article also discusses the concept of urban ecosystems and what functions they perform. The latest scientific studies on the growing interest in the problems of green infrastructure development in cities were analyzed. Fifteen principles of green urbanism are analyzed in detail and examples of how they are implemented in some countries of the European Union are given. It is proved that the implementation of the concept of "green" economy is possible only if state mechanisms are introduced to encourage investment in environmentally safe production. Attention is focused on the need to change the methods and forms of fiscal policy at the government level, adopt appropriate laws and regulations, radically reform the policy of subsidizing and supporting renewable energy sources, and further increase investment in the "green" sectors of the economy. It is shown that the development and implementation of the concept of "green" economy in Ukraine should be considered as the main reference point and the basis of state policy. To improve environmental safety in the capital, it is necessary to consistently implement a range of organizational, technical, innovative and other environmental measures with mandatory definition of the social optimum of environmental quality, which will be accompanied by increasing environmental costs and significantly increasing society's requirements for economical use.