The purpose of this research was to investigate the relationship between vegetation cover and soil characteristics in order to determine the most important soil factors which affect on quantitative variations and types of vegetation cover in the study area. The study area is located in west of Tehran province and southeast of Hashtgerd, next to Najm-abad village. After field studies, the index vegetation types were selected and randomized-systematic sampling method was used for soil and vegetation cover sampling in each key area. The area of each plot was determined according to type of plant species and their distribution using minimum area method. Some vegetation cover parameters such as canopy cover percentage, density and frequency of plant species were measured in the area. Then soil sampling were done from 2 horizons including 0-10 cm and 10-30 cm in each plot and soil attributes such as texture, pH, organic carbon percentage and gypsum were measured in the laboratory. Afterwards, statistical methods like multivariate regression, analysis of variance and RDA technique were used for analyzing soil and vegetation cover data. The results showed no specific difference between soil and vegetation data except for gypsum. In other word the effective factor on vegetation cover variation was soil gypsum.