According to the observational data in the northeast coast of Taiwan when the strong typhoon invaded, it was found that abnormal water variation happened several times, and all the abnormal water levels (storm surge) were higher than the normal engineering consideration. In this study, the variation of mean water level (wave set-up & wave set-down) due to progressive wave over a seabed with specific profile has been investigated. This specific seabed is simulated by the hydrodynamic physical models in the laboratory. Two kinds of experimental models are arranged; one is combined by three sections: slope, platform, and vertical wall, and another is combined by slope and vertical. Furthermore, two different slopes of 1/10 and 1/30 were considered. All experimental conditions were controlled such that incident waves break on slope and mean water levels were measured. In the first model arrangement, surf similarity parameter and dimensionless parameters form by incident and break wave condition are found to be functions of relative max mean water level, but when slope is steep(1/10), the relation between these dimensionless parameters is not obviously. In the second model arrangement, mean water level variation is compared with the theoretical value of single slope. When slope is mild(1/30), experimental results of mean water levels quit agree with theoretical value; when slope is steep(1/10), caused by the reflection of vertical wall, mean water levels in the break point and surf zone are different form theoretical value significantly.