The safety of hydrodynamic bearings can be significantly affected by base shock loads. This study focuses on investigating the shock dynamic characteristics of hydrodynamic bearings by combining the Euler equations, transient average Reynolds equation, and the asperity contact model. A tribo-dynamic model of hydrodynamic bearings under base shock load is established in this research. To validate the model, the corresponding drop shock tests are conducted on the hydrodynamic bearings, and the experimental and computational results show good agreement, confirming the reliability of the dynamic model. Building upon this foundation, a series of numerical simulations are performed to analyze the influence of various factors on the shock response of hydrodynamic bearings. The results indicate that the shock stiffness of hydrodynamic bearings gradually increases due to base shock loads. The anti-shock resistance capability of hydrodynamic bearings exhibits anisotropic behavior. Additionally, the shock stiffness also exhibits a nonlinear increase with the rotating speed. These findings contribute to a better understanding of the shock response of hydrodynamic bearings and provide valuable insights for designing hydrodynamic bearings with enhanced anti-shock resistance.