Abstract: By establishing the injection-production performance mathematic model of water-driving underground gas reservoir, this paper sets up the dynamic characteristics of pressure and saturation in reservoir when gas is injected. The minimum power consumption at compressor is taken as the objective functions in the summer, and the total amount of surplus natural gas in given period and pressure in each single well when injecting and the saturation confines are taken as restrict conditions, the optimum running modes in the summer is set up by use of composite optimum-regulating method, which provides a theoretical fundament for optimizing running mode of a practical underground gas storage in the summer.