[en] In this research, the extensive lowland of the Khuzistan in South West. Iran has been studied floristically. Brief information on climatic, topographic and lithologic aspects of the area are presented. Plants encountered in the area, based on collecting 1300 specimens are listed using the alphabetic system. The oil field areas, South West. Iran comprise three habitats: salt deserts and saline coasts, dunes and sandy soils, and finally marls, gypseous and calcareous places. Altogether 531 species from 351 genera belonging to 81 families were recognized in the study areas. For each species it's collecting places and habitat, life-form and phytogeographical region is cited