TYasuj city is the capital of Chaharmahal and Bakhtiari province and is located in the center of Yasuj plain. The development of Yasuj city has increased the possibility of pollution and vulnerability of surface and groundwater in the plain. DRASTIC method which is the most popular of overlaying methods apply in order to producing the vulnerability map of the Yasooj aquifer. Vulnerability Zoning map aquifer based on the integration of raster maps of seven DRASTIC Parameters (water depth, Aquifer recharge, environment, groundwater, soil type, topography, the saturated and unsaturated hydraulic conductivity) in GIS shows that16%, 3% and 1% of aquifer has moderate to high, high and very high risk of contamination, respectively and the rest are pollution-free or low pollution. To assessment the accuracy of the study, the vulnerability map was calibrated with the nitrate concentration and land use maps. The coefficient correlation vulnerability index is about 49%. Also, the results were evaluated by land use map, which indicate the acceptable accuracy of the model.