Abstract: The efficient operation of salt cavern gas storage, as an ancillary facility of the gas pipeline network, is of greatsignificance to ensure the stable gas supply of the pipeline network. Constant-pressure operation is a new gas injectionand production mode of salt cavern gas storage with fluid replacement, which is economic for the pressure in the cavern isstable, and no base gas is required during the process of gas injection and production. However, in this mode, a large amountof brine is required for the replacement of natural gas, and a very large storage space or treatment plant is required for thebrine produced during gas injection. Thus, the economy and operability of the mode will be reduced greatly. Herein, a newtechnology effectively combining the solution mining under gas (SMUG) and constant-pressure operation is introduced, with which not only the constant-pressure operation can be realized, but also no treatment is required for the replacementmedium. Therefore, the application of the new technology is very promising. The pilot test for the technology was carriedout in Jintan Salt Cavern Gas Storage in 2018, having a great success.