Kinetic studies on the adsorption of cr-amylase from Aspergillus oryzae on an anion exchanger, Duolite A-568, and a hydrophobic adsorbent, Duolite XAD-761, were performed in batch stirred tanks. The experimental results were fitted to a mathematical model where both external film mass-transfer resistance and pore diffusion were accounted. Furthermore, a Langmuir expression was calculated and introduced into the model to describe the extent of the adsorption equilibrium. The pore diffusion coefficient increased with temperature in both adsorbate/adsorbent systems. Also, the pore diffusion coefficient was found to be essentially constant, at each temperature, over the experimental cr-amylase concentration range studied. This suggested that pore diffusion was the only controlling mass-transfer mechanism inside the particles. The model reproduces satisfactorily the experimental results and, therefore, it can be used for design, simulation, and optimization purposes.