The working gas volume is still lower than the design value after nearly ten injection-withdrawal cycles in some of Dagang underground gas storage facilities in China. Multicycle dynamic analysis was conducted by focusing on the performance of underground gas storage facility, injection-withdrawal wells and observation wells based on the geological and production characteristics of the gas reservoir, and then the main influencing factors of the working gas volume were analyzed, including geological condition, water flooded degree, development mode of gas reservoir, injection-withdrawal well pattern and injection-withdrawal mode of underground gas storage. This analysis provides a scientific basis for operational management and design, and also for constructing the same type of underground gas storages.