The present study aim to examine mapping of uranium distribution in the Cuddalore district, Tamil Nadu, India. Uranium is a relatively abundant element with the highest atomic number of all naturally occurring elements. The occurrences of groundwater are identified porous formation and in fractured and the weathered hard rock aquifer matrix. The geology of the district underline by different range of age from oldest Archean rocks to recent sediments. The study area occupy in 3,678 Sq.km. Totally 93 groundwater samples were collected during Pre-Monsoon, 2015. The collected samples were analyzed for major cations and anions in standard scientific manner. U was analyzed by using laser fluorimeter. The uranium concentration in the groundwater of this region ranges from 0.1 ppb to 24.67 ppb with an average of 1.