Chemical Laboratories, Faculty of Engineering and Technology, Aligarh Muslim University, Aligarh-202001. Manuscript received 1 March 1977, revised 22 July 1977, accepted 80 August 1977 Investigations on the effect of time, pH, exchangeable cations, organic matter and temperature on the adsorption of telone on bentonite showed that a minimum period of 8 hours for hydrogen saturated and 10 hours for sodium saturated bentonite was required for completion of the process of adsorption. The adsorption of telone increased with a decrease in pH. The interaction was cation dependent and occurred mostly due to ion exchange. Organic matter in form of humic acid increased the degree of adsorption due to interaction of the telone molecule with organic matter. The process was temperature sensitive and decreased with a rise in temperature.