In order to study the characteristics of hydrodynamic hybrid bearings under shock load,a coupled model including dynamic time-varying Reynolds equation,film thickness equation,rotor dynamics equation,and boundary conditions was established for a hybrid bearing with deep and shallow pockets.The finite difference and Euler methods were used to calculate the hydrodynamic pressure distribution under shock load,and the influence of shock angle,length-to-diameter ratio,and radius clearance on the axis orbit and load carrying capacity was analyzed.The results reveal that the shock load with opposite directions and equal amplitudes result in symmetrical changes in the load carrying capacity and axis orbit of the hydrodynamic hybrid bearings.The larger the length-to-diameter ratio of hydrodynamic hybrid bearings,the smaller the peak change of the load carrying capacity under shock load. The smaller the radius clearance,the smaller the peak change of the load carrying capacity under shock load.These findings suggest that the bearing shock resistance can be enhanced by reducing the radial clearance and increasing the length-to-diameter ratio.