This paper presents the development of the Tsunami experimental device for education of earthquake disaster prevention. First, the process of development, especially trial making process of various devices is introduced. Next, the outline and the feature of this device are explained. Finally, an example of operating this device is shown. Up to now, there has been no device like this. That is, easy to carry, operate, and able to perform experiment by looking at the wave in the device. It is expected that everyone can easily learn scariness and the essence of the Tsunami with this teaching material.