Prussian blue and chitosan(PB-CS) composite film was prepared by potentiostatic deposition.Core/shell structure nano-TiO2@Pt composite was prepared and deposited on the surface of PB-CS composite film,which was utilized to immobilize glucose oxidase(GOD).nano-TiO2@Pt composite could obviously improve electrical conductivity of biosensor and amount of immobilized GOx.Furthermore,CS can effectively protect PB from leaking out,which could increase the catalytic activity of this biosensor.This novel glucose biosensor shows a good linear relationship with glucose concentration in the range of 1.2×10-6-1.1×10-3 mol?L-1 with a correlation coefficient(r) of 0.998 6.The limit of detection is 4.0×10-7 mol?L-1 and the sensitivity is 13.31 mA?mol?L-1?cm-2.The relative standard deviation for the method was 3.8% at concentration level of 0.3 mmol?L-1 glucose standard solution for 5 determinations.