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Land subsidence, as one of the most dangerous environmental phenomena, can occur for a number of reasons, including the over-extraction of the aquifer and the decline of groundwater level. Subsidence begins with vertical displacements and often causes trough, sinkhole, or deep cracks in the ground surface. The occurrence of this phenomenon in most cases causes damages that are often irreversible and costly. Therefore, for the sustainable development of the region, it is very important to accurately predict the occurrence of subsidence and controll it prior to its occurance. In recent decades, the drought and excessive extraction of groundwater resources, and as a result, the water-level decline, especially in dry and low rainfall regions, has been the main cause of this phenomenon in the plains of Iran. The aim of this study was to calculate the amount of subsidence due to the water table decline in Kashan plain. For this purpose, by collecting the required data, the groundwater has been modeled using GMS software, and based on that, the amount of subsidence during the last years has been determined. The results of this study showed that the land subsidence in the study area is increasing both in terms of quantity (from a few millimeters to several centimeters) and in terms of extent. The maximum subsidence was obtained as 5.95 cm. Therefore, it is very necessary that in addition to planned management and exact control on the exploitation of groundwater of region, academic studies, and quick actions be applied to provide the drinking and agriculture water required by other methods such as the water transfer from other areas.