Groundwater is an essential resource for rural households and the public in El Dir, Sohag Governorate, South Egypt. Groundwater is used for drinking and irrigation in the larger settlements. The Pleistocene aquifer is considered the main groundwater source in the El Dir area due to suitable groundwater salinity. Geochemistry has been used to examine processes impacting groundwater quality and to investigate the recharge source(s), the extent of water-rock interaction, and the mechanisms of mixing processes. The main sources of groundwater recharge are the seepage from the River Nile and the surface water drainage system. According to the geologic environment, major ions (Na+, K+, Ca2+, Mg2+, HCO3- Cl-, SO42-) and nitrogen compounds (NH4+, NO3-) the shallow groundwater quality in the El Dir area has been deteriorated due to the regional extent of water-rock interaction, anthropological activity, and mixing processes. The majority of groundwater salinization is caused by silicate weathering, and the components, including Na+, K+, Ca2+, and Mg2+ are mostly obtained from groundwater and aquifer lithology interacting (geogenic effect). Anthropological activities involve human activity, agricultural practices, and extensive uses of fertilizers. The mixing with wastewater infiltration leads to elevated nitrogen compounds in the Pleistocene aquifer. The groundwater in the El Dir area is suitable for agricultural uses; however, water treatment is crucial for human drinking to remove the impact of contamination with wastewater.