In the under-water explosion ship shock resistance test, the buffer platform is an effective tool for shock protection for the equipments. A small floating shock platform used as the test impact target, to test the buffering performance of the buffer platform under the explosion charge, with basic inputs of the buffer platform and the equipments on it being measured. The shock spectrum analysis method is used, to obtain the responses of the buffer platform. It is indicated that for the buffer platform, different damping ratios have a great influence on the platform equipment shock response; when the equipment has a large mass, the platform equipment response spectrum shows an apparent dip trend; in the equipment shock protection design, the effects of the mass of the equipment and the natural frequency on the shock spectrum should be considered, to reduce the design difficulty for the impact protection device.