In order to study the dynamic behavior of ship's side shell structures subjected to impulsive wave load, a test equipment was made as a part of research works of Japan Shipbuilding Research Association. Principal features of the equipment are as follows: The maximum dimension of test model is 1.5m square. The maximum pressure is 15kg/cm^2. The height and the diameter of the pressure chamber are about 6m and 2.8m respectively. The equipment is semi-automatically operated by sequence control system. Impulsive pressure patterns can be controled by ajusting factors such as water level, set-up pressure, thickness of rupture discs, rupture time difference of two discs and rigidity of test model.