A new hybrid model has been developed Diffuse Simulink to evaluate the levels of groundwater quality in the city of Tiruchirappalli, S. India. management of water quality is an important issue in modern times. The data collected Tiruchirappalli city have been used to develop this approach. This is illustrated seventy-nine samples Groundwater collected Tiruchirappalli Corporation, S. India. The characteristics of groundwater in the groundwater of the plain have been followed during the years 2006 and 2008. The quality of groundwater several stations were established in the floodplain were evaluated using Fuzzy logic simulation. The results of fuzzy logic and the study estimated the monitoring Simulink aa resulted in a good agreement. groundwater quality for drinking has shown high to moderate levels of water pollution in Srirangam, Ariyamangalam, and K. Golden Rock Abisekapurm around areas of study depending on factors such as groundwater depth, the components of groundwater and the vulnerability of groundwater pollution. Fuzzy Logic simulation approach proved to be a practical tool, simple and useful for evaluating the quality assessment of groundwater for drinking. This approach is capable view the evaluation of the quality of drinking water.