The Kaji salt playa is located in 65 km north of Nehbandan; Iran. In this research, the effect of hydrogeological and tectonic factors on the quality of groundwater in the coastal aquifer of Kaji playa has been discussed. Also, by using remote sensing methods on satellite images, the effect of tectonic factors on the quality of groundwater resources has been evaluated. In general, the direction of the groundwater flow is from the south of the playa towards its center, and during the years 1998-2018, the water table has dropped by about 2 m. The type of groundwater in all areas is NaCl type, same playa water. The histogram of electrical conductivity of water sources also shows the decrease in the quality of groundwater. Based on factor analysis, 3 effective factors have been identified as the main factor. The first factor is geological factors in the dissolution of soluble minerals as well as saltwater intrusion of playa. The second factor is indicative of human activities and the third factor is the effective factors in the dissolution of carbon dioxide gas in water. Among the hydrogeological factors it can be mention to the increase in well discharge and the volume of extraction from the aquifer, the increase in the depth of exploitation wells, reduce the distance of wells to the playa, and existence of short waterways. Finally, increase in the slope of ground surface as well as increase in shear and tensile lineaments are tectonic factors.