Dynamic response analysis of the ship structure is usually based on the assumption that the correlation between the pressure and the response is linear within the frequency domain. This report is concerned with that whether or not the above assumption is still applicable to the dynamic response due to slamming pressure of the bottom plate of the high speed craft. Drop test of the full-scale model of the bottom plate of high speed craft on the water surface is carried out and experimental results are compared with calculated results using the finite strip method. The pressure is expanded into Fourier series and the dynamic response is calculated as the set of the response under every frequency load. Then the effect of damping factor is investigated. Damping factor of this bottom plate is evaluated as 6π (= [ C ] / T [ M ]), which coincides with the results of flat plate. The root mean square of the deflection of the bottom plate is then calculated by using the power spectrum. The ratio of maximum deflection to the root mean square becomes about 3 on the middle of bottom plate. The coherence function, which is defined by the power spectrum and the cross power spectrum of the pressure and the response, yields to about 1. Therefore, linearity between the pressure and the response within the frequency domain is confirmed.