Uncontrolled urbanization of cities or towns, especially in Poland, and political needs cause an uncontrolled loss of green areas. Forests as well as the green areas of cities are one of the largest natural assets of large urban agglomerations. The need to expand large centers inhabited by people with infrastructure may be a threat to the existence of urban greenery. Hence, there is the need for a prudent and informed policy in the area of protection of the green metropolitan resources because of the human right to a healthy environment. The work concerns the analysis of EU and Polish law in connection with political assumptions and their impact on the protection of these green areas of European cities, with particular emphasis on Poland.