Deficiency of water with suitable quality is a vital challenge in urban and specially in arid and semiarid regions. The aim of this study is to assess temporal and spatial variation of drinking groundwater quality and quantity in County of Mallard in Tehran province. Mallard is a County at margin of Central Iran Plateau. The data used in this research comprises of 14 parameters in 31 drinking water wells that obtained during a 6-year interval. Spatiotemporal variation in these wells were analyzed by applying Parametric and nonparametric statistical techniques including one-way ANOVA, Kruskal-Wallis, independent-samples T-test, Mann-Whitney. The results reveals that concentration of sulfate, chlorine, bicarbonate, electrical conductivity, TDS, sodium and fluorine in dry and wet periods have significant difference. Effects of space on quality of groundwater in Mallard suggest that boring wells in pyroclastic, tuff and sandy lime (E₂) Formations meaningfully and at level of Percent 95 have the most impact on mineral concentration of water quality parameters. Furthermore, concentration of nitrate has increased in cultivation and urban-rural land use and the level of pH in cultivating and urban-rural use has decreased significant and at level of Percent 95 in comparison to other lands.