In the recent years, the over-use of water resource due to the population growth and industrial developing has become serious. With attention to demand for water, it's essential to explore and evaluate new water resource and mapping its potential. In this paper, a fuzzy set theory, as a knowledge driven approach for map combination, was applied to produce a potential map for ground water resources. To achieve this objective, a variety of spatial data including geology, slope, elevation, drainage, fault and joint were complied. Then fuzzy membership functions were evaluated for each data layer. These data were integrated using the fuzzy  operator with a value of  = 0.95. The final map indicates Quaternary formation consists of alluvial deposits near the 200 meter distance from the anti-cline as a suitable area for groundwater resource. Finding out an accurate method which accelerates processing for determining the location of groundwater before drilling is an effective solution leading to save budget and time