Electropolymerized polypyrrole-biotin on carbon felt has been processed as filtration membranes immobilizing biotinylated enzymes (peroxidase and catalase) by the avidin-biotin recognition process. These membranes are shown to be efficient systems for hydrogen peroxide dismutation because the concentration of active enzyme in the membrane, is high in comparison with that obtained by current techniques for enzyme immobilization. A Michaelis-Menten kinetic analysis type is proposed, which demonstrates that even if the rate of the enzymatic process is decreased in the membrane environment, the corresponding decrease of the rate parameters is no more than a factor of four compared with values in solution. The long-term stability and reactivity of the enzymatic membrane were also shown to be significantly improved compared with other types of routes for enzyme immobilization.