Abstarct: The Sarchehan Plain in Fars Province, being located in a semi-arid region, faces the challenges of water shortage and groundwater level decline. The study of the hydrogeological balance of this plain is of great importance in order to examine the balance between water inputs and outputs and identify the factors affecting it, and is one of the objectives of this research. In this research, statistics from 19 observation wells from 1376 to 1400 were used. The general trend of groundwater flow is from the northern and northwest parts to the south and southeast. The hydraulic gradient is higher in the northern parts and the output of the plain and lower in the central parts due to the concentration of wells. In this plain, the presence of a river has also affected the direction of flow to some extent; in such a way that it plays the role of a receiver in the upstream part. The depth of groundwater varies between 15 and 45 meters in this plain. Also, according to geophysical studies, the thickness of sediments in this plain varies between 60 in the northern and border areas to 100 meters in the central and western areas. According to 24-year data on changes in piezometric water level, piezometers in the eastern half of the aquifer with an average drop of 15 meters have had a greater drop compared to the western piezometers with an average drop of 11.5 meters, which can be attributed to the greater exploitation of wells in this part. According to the hydrograph of the plain unit, the general trend of changes in water level in the studied plain is downward. However, in the years 1376 to 1378 and around 1384, the trend of changes was upward due to higher precipitation, which could possibly be due to the higher water level in those years and the smaller thickness of the unsaturated zone and the faster response of the water level to precipitation recharge. The deficit of the Sarchehan aquifer reservoir is estimated by the balance method for the water year 2000-99 to be 12.54 million cubic meters. Excessive withdrawal and lack of precipitation are the reasons for this change.