The increasing water demand has led to heavy exploitation of groundwater resources in many parts of the country, particularly in the hilly regions. The water resources available in the hilly regions and are restricted to groundwater sources due to higher slopes. The major source surface water bodies such as rivers, lakes, springs etc is rainfall and minor is glaciers. The study shows that isotopic composition of precipitation shows depleted nature during monsoon period due to moisture source from the oceanic region and enriched isotopic composition during non-monsoon period due to moisture source from westerlies and local evaporation. The study also represents that the temperature shows expected positive and negative relationship with individual locations. Studies conducted worldwide during last few decades have established that stable oxygen and hydrogen isotope ratios provide useful tools for hydrological. In case of groundwater, stable isotopes have been used to estimate recharge rates and to identify the recharge zones, to determine the affect of evaporation on groundwater system, to estimate diffusion rates in unsaturated zones, to study the groundwater surface water interaction and to identify source of salinity (Bhattacharya et al., 1985, Navada et al., 1986; Deshpande et al., 2003).The stable isotopic characteristics of Himalayan River namely, Ganga, Yamuna and Indus.