The bionanocomposite film consisting of glucose oxidase/Pt/functional graphene sheets/chitosan (GOD/Pt/FGS/chitosan) for glucose sensing is described. With the electrocatalytic synergy of FGS and Pt nanoparticles to hydrogen peroxide, a sensitive biosensor with a detection limit of 0.6 microM glucose was achieved. The biosensor also has good reproducibility, long-term stability and negligible interfering signals from ascorbic acid and uric acid comparing with the response to glucose. The large surface area and good electrical conductivity of graphene suggests that graphene is a potential candidate as a sensor material. The hybrid nanocomposite glucose sensor provides new opportunity for clinical diagnosis and point-of-care applications.