This paper describes the results of hydrogeochemistry to generate baseline information on hydrochemical evolution of the groundwater is related to the flow path of groundwater. The Gadilam River Basin in Tamilnadu is characterized by different geological formations like, and groundwater is the major source for domestic,  agriculture  and  other  water-related  activities.  The  chief hydrogeochemical facies of the groundwater is Na-Cl. The waters are subjected to evaporation or evapotranspiration process tends to remove ions from the waters for formation of new clay minerals and precipitation of CaCO3. Comparison of river water with the groundwater reveals that recharge of river water into the groundwater system during post monsoon period. The study with mixing model exhibits higher percentage of mixing of parent solution in the North West part of the study area.