In recent years, hyper-elastic materials have been widely used in transmedia bionic flexible body submersibles, and the transient slamming load at water entry may cause structural damage. In this paper, based on the meshless fluid-structure interaction numerical simulation method, the Weakly Compressible Smoothed Particle Hydrodynamics (WCSPH) is used to simulate the fluid motion and the Lagrangian characteristic is easy to trace the deformation of the free liquid surface. The Smoothed Point Interpolation Method (SPIM) based on the gradient smoothing technique is employed to analyze the structural response, which can resist the mesh distortion caused by the large structural deformation. The water-entry slamming problem of hyper-elastic plate is investigated to analyze the characteristics of fluid field, the slamming load evolution law and the structural dynamic response characteristics under different material properties, velocity and angle, to reveal the water-entry mechanism of the bionic hyper-elastic material.