It is a basic process, distinguishing of water based on quantity and quality properties and condition of it reach for consuming optimum. It has been to descent processes the level of underground water according to simple hydrograph of Shiraz plain in statistical period of 1993-2011 that totally the level of underground water has been decreasing about 5.98 meters. It has been decreased the quality of aquifer in studied period simultaneously with quantity. It was confirmed that result in survey of quality of underground water by using of Man-Kendall test. It was concluded that the plain aquifer was in two classes of C3S1 and C4S1 according to classification of irrigation water based on Wilcox theory in this time that it has salinity and very salinity water. It is in class of unacceptable, proper the plain with water based on Schuler classification in this time. The correlation results showed that level of underground water for water quality parameters had a significant negative correlation in level 99% and no significant correlation for precipitation. Manuscript profile