During the peak-shaving, gas is frequently injected into and extracted from the cavern, which causes the temperature field of the gas and surrounding rock to undergo periodic changes with the gas injection and extraction. The mechanical properties of rock salt are quite sensitive to temperature. Existing research results show that the creep rate of rock salt increases exponentially with temperature, which can easily cause excessive shrinkage at the chimney. Temperature changes can also cause thermal stress in the surrounding rock, affecting the prediction accuracy of salt cavern gas storage capacity. This chapter proposed an unsteady heat transfer model for the gas-wellbore-salt cavern system during gas injection and withdrawal to reflect the thermal behaviors between gas and surrounding rock, particularly the gas Joule-Thomson effect during gas operation. Then, a fully coupled numerical solution method based on a unified matrix is presented, and a novel numerical simulation software was developed. This chapter highlighted the engineering value of the gas flow and heat transfer model, which could be potentially employed to predict temperature field, pipe leakage diagnosis, and prediction of gas storage capacity.