Abstract: Through evaluation the sustainability of natural resources expressed by theireconomic value,it is helpful to chang the free using natural resources to non-gratuitous system in order to sustain the productivity of the natural resources.Method and theory for evaluation the ecomonic-value of the natural resources were analysed in the paper,and date collected from a pilot field in Baiquan County was analysed and calculated by a method called Natural Resource Depreciation.The results proved the effectiveness of the method.