J. Panahy , A. Mahmudzadeh , A. Hasanzadeh , Presentation of Plant Communities in Razhan Region, Research Journal of Biological Sciences, Volume 3,Issue 2, 2008, Pages 211-213, ISSN 1815-8846, rjbsci.2008.211.213, (https://makhillpublications.co/view-article.php?doi=rjbsci.2008.211.213) Abstract: The present research was carried out in order to figure out the plant communities of the Razhan region and ecological factors that affect them. Razhan region with an area of 1667 ha is located in northwest of Iran in west Azerbaijan province. In this manner, plant communities was determined by Floristic- Physiognomic method and the similarity between plant communities was calculated by use of Sorensen` s similarity index. In general 319 species belong to 195 Genera and 45 Families was determined during floristic study in the area and 15 plant communities, was determined. The main ecological factors that affect vegetation of the region are: Altitude and biological factors. And slope and aspect are in the next order. Keywords: Plant community;ecological factors;Razhan;Iran