The dynamic behavior of a fully clamped rectangular plate impacted by a rigid knife-edge is studied in this paper. Based on the variational finite difference method, a numerical model of dynamic inelastic response of plates impacted by a rigid knife-edge indentor is being developed, which includes the influence of finite transverse displacements, axial restraints, bending moments, material elasticity and strain hardening. The struck plate and rigid striker were coupled in the numerical simulation, with the deformation, strain, stress and impact force as outputs of the calculation. Numerical results were given on a small-scale ship model test, which provides a full picture of the response of the clamped rectangular plate under dynamic load. It provides information on the impact force, deformation, stress and strain everywhere in the plate. Such data could not be obtained experimentally or by simple plastic formulations.