Using underground salt cavern for oil and gas storage is a common practice. Due to the characteristics of underground salt mines in China, which are rich in bedded salt rock, thin in terms of thickness and combined with high volume of insoluble non-salt rock, the shape control of single-well cavern construction is inevitably difficult and the construction takes a long time. Using experimental simulation construction of the horizontal salt cavern as a basic model, and taking the geological and physically mechanical conditions of salt caverns in Yunying, Hubei province into consideration, we numerically simulated the long-term rock creep effect under different buried depths with the twin-well cavern construction method. The simulation results show that the construction method is applicable, and the shape of cavern can be controlled through flow and fluid interface. It's also found during the same time in which rock creep takes effect, the deeper the cavern is buried, the higher the shrinkage rate of the cavern is, and the larger the plastic deformation zone around cavern becomes, which finally result in the shorter service life of the salt cavern for horizontal gas storage.