The Asteraceae family is one of the important families of gamopetales flowering plants which are containing 1535 genus and 23000 species approximately. The genus Gundelia belongs to Asteraceae family that they have been distributed in mountainous area and semi desert and temperate climates. In flora of Iran has been reported only a species of Gundelia genus. Chaharmahal Bakhtiari province and the southern part of Isfahan province are situated in Central Zagros area that there are habitats of Gundelia tournefortii L. in parts of these areas. This study was aimed “Effect of Environmental Condition on Phytochemical Characteristics of Gundelia tournefortii L. in Chaharmahal Bakhtiari Province”. Samples of Gundelia tournefortii L. were taken from 4 sites in Chaharmahal Bakhtiari province (Taghanak-Shahrekord, Dastena-Keiar, Hircan-Farsan and Sheyda-Ben) and a site in the southern part of Isfahan province (Komeh-Semirom) and the most important chemical compounds in the essential oil of species were determined. For the extraction of essential oil, was used Clevenger apparatus by hidrodistillation method and for chemical compounds determination, was used GC/MS. 310 compounds in the essence of this plant in habitats of the Chaharmahal Bakhtiari province and 118 compounds in the essence of this plant in habitat of the southern part of Isfahan province were identified in which the major compounds were Palmitic acid, Phytol, Lauric acid, Linoleic acid, ? Ionene, Myristic acid, Hexahydro farnesyl acetone, 1-Hexadecanol, 2-methyl, ? Turmerone, Linolenic acid methyl ester, Linolenic acid ethyl ester, S beta aminoethyl thiosulphoric acid, Octadecane and Tridecane. The most important of ecological features of sites was determined in three sections of physiographic, climate and soil. To study of existence similarity between sites and their Keywords : Gundelia tournefortii L, Essential oil, Ecological factors, Ordination, Cluster analysis, Chaharmahal Bakhtiari province, Isfahan province