Defluoridation of drinking water was carried out by the continuous down flow adsorption mode at room temperature. Five columns were prepared by the impregnation of ZrOCl2, CaO, Alum, CaCl2 and Borax in activated coconut shell charcoal. Known fluoride influent water was run into the column at a constant rate of 4.0 L/h and a constant level of water was maintained. Samples of the treated water were collected for analysis by the ion selective electrode method. In this study zirconium ion impregnated coconut shell charcoal (ZICSC) showed maximum fluoride uptake and proved to be the most effective defluoridating agent followed by CaO and Alum.