The adsorption thermodynamics of carbofuran has been studied on antimony (V) silicate cation exchanger at 30 and 50 degrees C. The adsorption isotherms of carbofuran have been found to follow the Freundlich adsorption model and yield "S" class isotherms. The order of adsorption of carbofuran is in accordance with the partial molal free-energy changes in the exchanger. The thermodynamic equilibrium constant (K0), standard free energy (delta G degrees), enthalpy (delta H degrees), and entropy (delta S degrees) changes have also been calculated for predicting the nature of adsorption.