Abstract: The propagation characteristics of microwave magnetostatic waves (MSWs) in the magnetic film under arbitrary DC bias field are analyzed. The bandwidth, radiation resistance and insertion loss of magnetostatic forward waves propagated in the YIG film are calculated. It is indicated that under arbitrarily inclined magnetic field the radiation resistance of MSWs propagating in the different direction are not equal, which is obviously different from the case of normal magnetization; and that the insertion loss can be decreased under appropriately inclined bias magnetic field, so that the diffraction effect of guided optical waves in MSW-based Bragg cells is also enhanced.