Theoretical solutions exist for the contact explosion of circular plates in air under certain assumptions, however, in aqueous medium, it is hard to derive theoretical solutions in near field. This paper studies the impact effect of underwater explo- sion loads on the circular plate at water surface by the LS-Dyna whole process simulation technique under near field conditions, ob- tains the change law of typical parameters such as free field pressure, bubble’s pulsation period and maximum radius, and water jet velocity, which are consistent with the results of theoretical analysis. The changing process of the pulsation form of bubble in the first cycle is revealed, and structural stress response and structural deformation of circular plate are obtained. This method can be further applied to damage assessment of surface ships under near field underwater explosion.