In this study, poly(diallyldimethylammonium chloride) (PDDA) was selected as an electron acceptor for functionalizing graphene. The resultant PDDA functionalized graphene (PDDA-G) was characterized using TEM, UV-vis absorption spectrum, Raman spectrum and electrochemical method. The PDDA-G modified electrode displayed remarkable electrocatalytic activity toward H2O2 reduction and can be used as a nonenzymatic biosensor for H2O2 detection. Then negatively charged glucose oxidase (GOD) was immobilized onto the positively charged PDDA-G matrix driven by electrostatic interaction. This novel GOD/PDDA-G bionanocomposite can be used as a biosensor for the detection of glucose with a linear range from 0.02 to 1.8 mM and a detection limit of 8 a,M. In this report, the biosensors are easy to prepare, have good stability, and will have potential applications in H2O2 and glucose sensing. (C) 2013 Elsevier Ltd. All rights reserved.