Ground water is an important source of water supply throughout the world. Its use in irrigation, industries, municipality and rural areas continues to increase. The need of the groundwater exceeds the groundwater potential and water scarcity exists. It becomes essential to evaluate qualitative and quantitative assessment of existing ground water resources. Mailam Block of Tindivanam Taluk, Villupuram District, falls between the latitudes 79⁰26' to 79⁰44'N and longitudes 12⁰3' to 12⁰19' E and forms part of survey of India Top sheet No.57 P/12. Ground water sample from 30 locations have been collected and analyzed and brought into a digital output using a simple program HYCH. From the digital output, thematic maps such as Total Dissolved Solids (TDS), Total Hardness, Corrosivity ratio, USSL Classification and Groundwater Classification have been prepared using the GIS environment. It is inferred that the quality of groundwater is very poor in central part of the study area. High TDS water occurs in locations near eastern and western part of this region. Groundwaters in many parts of the study area are of hard water type. Entire northern and central portion has highly corrosive water. C5S4 water occurs in central zone is unfit for the agricultural use rest of the area have better quality of water which can be used for certain agricultural purposes. Designing of recharging wells along the central region will result in considerable improvement both in the quality and quantity of groundwater.