Iran is a vast country with special conditions in terms of geographical position, climatic diversity and topography that has led to a high diversity of flowering and nonflowering plants. Without deep, reliable and accurate study of vegetation, the exact recognition of plant species and plant biodiversity of Iran as well as any planning for the development and management of natural resources in the country is impossible. Therefore, this approach led to the establishment of the National Botanical Garden of Iran in 1968, and then continued to operate as the Botanical Institute of Iran. It joined the Research Institute of Forest and Rangeland in 1979 and currently working on her duties as the "Botany Research Division".