The WO_3film has moderate optical band gap,refractive index and high work function and other semiconductor characteristics.In this paper,sputtering is used to prepare the WO_3film to test its optical and electrical properties , and the appearance structure and crystal state of the film are observed using AF M and XRD.XPS and UPS characterize the stoichiometric composition and work funct ion of the film,and apply WO_3film to AlGaInP light-emitting diode devices to i ncrease the ohmic contact characteristics with p-GaP and increase the carrier i n jection efficiency;the test results show that:The composite film formed by the thick WO_3film dummy layer and ITO can effectively increase the electron inje ct ion efficiency,increase the light intensity of the AlGaInP light-emitting diod e by 4%,and reduce the forward voltage by 0.01V.