Abstract: The dynamic response of a cylindrical explosion containment vessel with the elliptical cover under four kinds blast loading was studied using explicit finite element code LS-DYNA. The results show that for the ideal structure that only include a cylinder and an elliptical cover, the strain of the points on the plane which across the center of the vessel has become the largest during the initial stage. When adding a certain mass flange on the vessel, the strain growth phenomenon has shown up on the above points. The strain growth and the mass of the flange are the factors that must be considered when designed.