The area for the present study comprises, Pallavaram, Chromepet, and Nagalkeni, of the Chennai Metropolitan City. Thirty six groundwater samples were collected from open and bore wells during Pre-monsoon (July 2007) and Post-monsoon (January 2008). The parameters like EC, TDS, pH, Ca, Mg, K, Na, SO₄, Cl, and HCO₃ were determined by using standard methods of analysis. The trace elements like, Cu, Cr, Ni, and Pb were determined by using Atomic Absorption Spectrometer. Most of the standard parameters determined in the study area were above the permissible limit. Parameters like sodium, chlorine are found far above the permissible limit, especially in areas near the industrial sites. The type of water that predominates in the study area is (91.7%) Strong acids (Cl) exceed weak acids (HCO₃ and SO₄) during pre-monsoon and (100%) Strong acids (Cl) exceed weak acids (HCO₃ and SO₄) during post-monsoon based on the hydro-chemical facies. The chromium content was far higher than the permissible limit. Leather and cosmetic industries in the study area has deteriorated the quality of groundwater considerably. Thus, this study indicates the impact of effluents from tanneries. The groundwater quality of this region can also be improved by adopting rainwater harvesting thereby increasing groundwater recharge.