Due to the monsoon changes and the failure of rainfall the drinking water scarcity become the most important problem. The groundwater is one of the most important sources for drinking water nowadays. However due to the dumping of municipal wastes and agricultural wastes in to the ground and industrial waste water into the river leads to the contamination of groundwater. Thus the analysis of the groundwater quality is very important to protect the human health. So in this study an assessment of groundwater quality is conducted in and around Namakkal district, Tamilnadu, India. About twenty samples were taken from the wells and bore wells throughout the Namakkal district with necessary precaution and the physico-chemical and biological characteristics are analyzed.