In this study, magnetic graphene oxide functionalized with amine-terminated poly(amidoamine) dendrimer, decorated with palladium nanoparticles (GO-Fe3O4-PAMAM-Pd) has been utilized for non-enzymatic electrochemical determination of hydrogen peroxide (H2O2). For this purpose, the GO-Fe3O4-PAMAM-Pd composite material was immobilized on a glassy carbon electrode (GCE) and its electrocatalytic activity toward H2O2 reduction was evaluated with cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods. It was found that the presence of uniformly dispersed Pd nanoparticles on the magnetic GO nanosheets play a major role in the electrocatalytic performance of the constructed electrochemical sensor. Under optimum conditions, the designed sensor showed good electrochemical performance toward H2O2 reduction, offering extended linearity of 0.05 to 160 mu M and a low detection limit of 0.01 mu M. Besides, the sensor revealed good anti-interference property and high sensitivity toward H2O2 detection. The proposed electrode was also credibly employed for the determination of H2O2 in real water samples.