Abstract: In order to explore the effect of the boundary on the pulsation of underwater explosion bubble, the model of the bubble pulsation dynamics of an underwater explosion was proposed, based on the potential flow theory and considering the effects of proximity of the explosion bubble to a horizontal rigid plane, vertical migration of the bubble due to the hydrostatic imbalance. A computer program was used to solve the model. The pulsation dynamics, the distributing of velocity and pressure in the flow field and the loading of bubble pulsation were analyzed. The results show that the model can correctly describe the dynamic characteristics of the explosion bubble and the liquid around it. Quantificational results can be obtained by solving the model.