Groundwater in Assiut governorate has a particular importance where it is the second source for fresh water used for drinking, agricultural, domestic, and industrial purposes. Three hundred and thirty five wells were available during the period 2006 to 2009, and were subjected to analysis for chemicalcharacteristics. These data has been used to conclude two main results; the first one is preliminary evaluation of suitability of groundwater for drinking and irrigation purposes by
comparing those parameters with world health organization (WHO)
standards and Egyptian standards. the second one is building the correlation matrix between the groundwater quality parameters which are major ions, EC, TDS, SAR, Na%, RSC, TH, KI, PI, MH, CAI, and C.R. with comparing chemical parameters with
WHO (1996) and Egyptian standards for drinking, it shows that concentrations of Na+, K+, Ca2+, Mg2+, Hco3-, SO42−, and Fe are lower than the permissible limits in 80% of well s. Groundwater wells were classified according TDS as about 93 %
of wells have TDS less than 3000 mg/l, thus groundwater is suitable for irrigation.