Fast and unplanned city growth, has effects such as isolation of village societies, threatening urban cores and centers and small and weak societies, destruction of open spaces and open and natural regions. Smart growth offers a sustainable way for urban developing with appropriate use of available sources, increase of urban services, developing neighborhoods with different uses, making public transportation available and integrated designing in human scale. Green belts idea,at first was based on controlling the growth between cities, preventing from merging cities and separating specifications and details of city and village from each other. Although according to the fact that, there was not an agreement regarding the possible outcomes of green belts and controlling cities growth process among city experts, some with conservative ideas, believed that green belts are stopping barriers and negative factors in natural growth process of cities and some others, thought that it is element of separating urban and non-urban habitats. In first approved comprehensive plan of Tehran (2006), suburban ranges were recognized as protected range for future city developing. This definition has no more places according to the problems of Tehran. In this article based on the natural and environmental potentials of Tehran protected areas (Green belt) and many threats for its exposure to residential construction, there are offered strategies and protecting rules with smart growth approach and green belt definition.
