Abstract: Changes in the injection and production cycle of the underground gas storage with salt caves will cause periodic changes in the temperature and pressure of gas in the cavity, which will cause thermal stress in the surrounding rocks, endangering the safe operation during injection and productionin gas storage. Based on the theory of variable mass thermodynamics, the paper derives the differential equations of the gas temperature and pressure in the cavity changing with timeat avariable injection-production ratio, which are further verified by the existing research examples. Based on the thermal-solid coupling model of single cavity, a study is performed on the impacts of thermal effect, injection-production ratio, and thermal conductivity of salt rock on cavity stability during gas injection and production, respectively. For the process of gas injection, the thermal effect, and an increase in the gas injection rate and the thermal conductivity of salt rock help to avoid tensile damage in surrounding rocks and maintain the stability of the cavity. For the process of gas production, the thermal effect, and an increase in the gas injection rate and the thermal conductivity of salt rock will aggravate tensile damage in surrounding rocks, which is not conducive to cavitystability.