The problem of volume loss and cavern damage of salt cavern gas storages has been studied over many years. Using the Jintan salt cavern gas storage X as an example, a three-dimensional geometrical model was established according to the sonar cavity test results, and a nested double meshing was applied. Numerical simulation of gas storage operations over 10 years has been carried out. By studying the volume deformation and damage of salt cavities in different operating years under periodic injection and production conditions, the weak area of cavity stability during gas storage operation is predicted. The results show that compared with the upper part of the cavity, the displacement deformation of the smooth position of the cavern waist is smaller; With the continuous increase of working life, the displacement and deformation of the cavity wall at the same position gradually increase, and the rate of deformation increase gradually decreases; After 10 years of operation, the volume loss rate of gas storage reaches about 7%, and the volume loss of gas storage tends to slow down in the following years; The protruding position of the cavity wall from the middle of the salt cavity to the top plate is the weak area of the stability of the gas storage cavity, which should be avoided in the cavity design of the salt cavern gas storage.