Silver nanoclusters (AgNCs) synthesized by using polyethyleneimine as a stabilizing scaffold have been confirmed as a novel material to exhibit high electrocatalytic activity for the reduction of hydrogen peroxide in this paper. The novel hydrogen peroxide electrochemical sensor was originally prepared based on the excellent electrocatalytic activity for the reduction of hydrogen peroxide at the polyethyleneimine-templated silver nanoclusters modified glassy carbon electrode (PEI/AgNCs-GCE). To achieve the optimum electrocatalytic activity for the reduction of hydrogen peroxide, the pH of the buffer solution and concentration of immobilizing AgNCs solution were optimized. Under optimum conditions, the PEI/AgNCs-GCE revealed a highly linear response to H2O2 in the concentration of 10-1440 mu mol L-1 with a detection limit of 1.8 mu mol L-1. Compared to some silver nanoparticles modified electrodes, the novel electrochemical sensor based on AgNCs exhibited a better electrocatalytic activity for the reduction of H2O2 and a lower detection limit for the determination of H2O2. (C) 2013 Elsevier B.V. All rights reserved.