When a solid body impacts quiescent water at a certain velocity, the resultant surface-seal splash deforms and closes above the free surface. This study investigates the dynamics of the surface-seal splash by using a high-speed camera and particle image velocimetry (PIV) measurements. Based on PIV, an analytical model is developed to understand the mechanics of the surface-seal splash. The results indicate that the theoretical splash shapes are consistent with the experimental results. In addition, the effects of gravity, drag, surface tension, and aerodynamic pressure on the dynamics of surface-seal splash are also assessed, and the results indicate that the aerodynamic pressure plays a dominant role in the formation of the surface-seal splash.