Amylases are among the most important hydrolytic enzymes for all starch based industries. In this light, the encapsulation of microbial amylases by sol-gel method has drawn an increasing interest. The aim of this paper was to find the optimal sol-gel process for the entrapment of α-amylase. Three different methods to immobilize α-amylase were used: entrapment, by sol-gel method, adsorption and entrapment/deposition. The enzyme was entrapped in silica matrices by sol-gel method, at different water/TEOS ratio and different enzyme loading, in the presence of stabilizing agent. The activities of the immobilized α-amylase were assayed and compared with that of the native enzyme. [ABSTRACT FROM AUTHOR]