Abstract: By using the numerical simulation method,the transient response of a wide-chord hollow fan blade was investigated under the atmospheric flow field.The deformation response of the wide-chord hollow fan blade was obtained under unsteady boundary conditions with the fluid-structure interaction numerical simulation method.Computational results show that,under the action of the air flow field,the largest displacement occurs in the top of the front blade and the stress concentration is resulted from the superposition area along the spanwise direction including blade and core,with the stress decreased gradually from surface to inner of the blade.The stress concentration occurs in the blade surface while the distribution stress is relatively small and the core is relatively thin.The modal shape of the blade structure has not been well distributed along the circumferential direction due to the coupling effect between the aerodynamic force and the blade structure.When the fan blade is under fluid-solid coupling,the bending vibration is significant and close to the first-order vibration mode.