Shenzhou Geothermal Field is one of the geothermal fields with better water quality and higher water temperature in North China region. In order to realize the substainable development of geothermal resource, the effect of fault structure and thermal reservoir permeability to the water level decrease was analyzed in the paper, and the rational well spacing was investigated through the method of water level cut back of the interference well. The parameters of geothermal resource substainable development were obtained such as the allowable yield, the allowable well spacing density, the rational well spacing and so on.