Bstract: The applicability and effectiveness of setting springs and dampers on the exterior surface of a blast door to increase its resistance were investigated theoretically and numerically. A simplified equivalent three-DOF system of the blast door with springs and dampers was obtained using Lagrange’s equations. The effects of the stiffness coefficient, damping coefficient and mass ratio on the dynamic response of the blast door are analyzed. The theoretic results showed that only in case of small values of the stiffness coefficient and damping coefficient, the displacement at the mid-span of the main door can be reduced effectively, but the displacement of the structure attached on the top of springs and dampers was too large to be used in practical engineering. the resonance phenomenon between the blast door and the attached structure takes place in the case of larger values of the stiffness coefficient and smaller value of the damping coefficient; in the case of values of the stiffness coefficient and damping coefficient large enough, the effect of the above measure on the increase in the resistance of the blast door is still limited. The elaborate non-linear finite element analysis results of the typical flat and arch type blast doors further verified the above theoretic results. In conclusion, theoretical and numerical analysis both showed that emplacement springs and dampers on the top of the blast doors can not increase their resistance to nuclear and conventional blast loads effectively.