In order to improve the safety and reliability of fuze's flame-proof mechanism, a novel explosion venting mechanism was designed. A nonlinear finite element software ANSYS/LS-DYNA was applied to perform numerical simulation of reliability of the mechanism. The measurement results of experiment essentially agree with the simulations. The results show that after accidental detonator explosion there is no evident damage on the hydraulic lever by using blast deflector and the detonating tube is fully isolated without being affected. This novel mechanism can meet the demands of safety design of explosive train. Moreover, under the condition of achieving flame proof, aluminium hydraulic lever has the advantages of easy processing and low cost over the steel equivalent.