There are large numbers of brine-extracted caverns which can be reconstructed as the nature gas storage in the exploited salt mine. It can availably shorten the construction time of natural gas storage and eliminate the disadvantaged effect of brine-extracted caverns to the environment. Based on the geological data of the salt mine and the mechanical behavior of salt rock

the four brine-extracted caverns which will be reconstructed to the nature gas storages are studied by the three-dimensional numerical simulation. The stress state around the caverns and the volume convergence law of the caverns are studied under the various gas recovery velocities. The better conclusion about the optimized gas recovery velocity of natural gas storage is obtained by the research.