The work aims to provide a basis for the design of seal structure of accident-resistant packaging container. The design of two kinds of seal structures for accident-resistant packaging container was introduced. The deformation of sealing face and the change of compression rate of the O-ring after accident scenario were analyzed, and then the sealing performance tests were conducted. When end face seal structure was subject to accident scenario, if the compression rate of O-ring was no less than 15%, the leak rate of seal structure detected was the environment background leak rate. When the compression rate dropped to 10%, the leak rate increased considerably, but it could still reach an order of magnitude of 1 μPa•m3/s. When the compression rate dropped to 5%, the seal structure failed completely. For the cylindrical face seal structure, even though all its connecting bolts failed after the accident scenario, the sealing performance of seal structure basically remained unchanged, and the leak rate detected was the environment background leak rate. The ability of the cylindrical face seal structure to resist accident risk is stronger.