Abstract: It’s a key step to reduce the subsurface water level in the construction of large building’s foundation. In combination with several engineering examples, this paper described the method of “Ripe-Well” reducing the water level from the respect of hydrogeology, technical demand, construction key point and monitoring management of reducing the water level and so on. The result shows that the method can effectively reduce the water level, ensure the high quality of the foundation constuction and complete on time.