Increasing population and global warming have increased the need for quality water resources for various agricltural, drinking and industrial uses.Groundwater is one of the main sources of water supply, the quality of which is affected by changing natural and human factors. Groundwater is facing problems such as declining water levels, declining nutrition due to declining rainfall and declining quality due to natural and unnatural pollutants. Declining groundwater levels will also cause subsidence and saline water advancement. The Mann-Kendall test is one of the most important tests to detect trends in the data time series. 6-year time was used in 20 piezometric stations. The results showed that in the study area, there is no specific trend on changes in groundwater aquifer level, so that in some stations the trend is increasing and in some decreasing trends and in others there is no trend. MLP and RBF neural network models were then used to qualitatively simulate aquifer. First, due to the large number of data with the help of cluster analysis, the data were divided into 3 clusters, and in each cluster, 30 architectures were examined in MLP and RBF models, which is more efficient among the algorithms used. It had more hyperbolic function than other algorithms and also among the functions.Finally, using geostatistical methods, spatial changes in groundwater quality in Shiraz plain were investigated. In this study, in order to evaluate the interpolation methods, the values ??of mean absolute error value, mean error deviation, and square squared error were used. The kriging method had a higher accuracy than the IDW method. Finally, the zoning map was prepared using kriging method. Cracking maps show that the highest salinity is in the eastern, northeastern and central regions of the plain, which has been increased significantly in 2016, as well as the highest concentration of nitrate in the eastern part of the plain for 2015. According to the results, the amount of excessive use of chemical fertilizers in the study area has been an important factor and affect the groundwater quality of the plain. Keywords : Nitrate, Electrical conductivity, Salinity, Groundwater, Artificial neural network, Mann-Kendall test, Kriging