For through-the-canopy-ejection-saving system with miniature detonation cord (MDC), screw/seat system has penetrated canopy to successfully escape after the strength of canopy weaken by MDC in the case of emergency. Injury of human head and spine is serious due to striking between aircrew/seat and canopy during the ejection. In the paper, considering MDC installed along all-around of canopy, the initial cut slot is used to model the damage of canopy impacted by detonation wave from MDC. Simplified finite element model of through-the-canopy-ejection-system has been established according to ergonomics. In FEM, canopy as PMMA employs elastic viscoplastic material model combined with continuum damage mechanics, crew is modeled as 50% deformable dummy. FEM is solved using nonlinear dynamics explicit code LS-DYNA3D. Head impact force and dynamic response index (DRI) of spine are obtained, and meet the requirement of nation army standard. Simulation results indicate that MDC installation way is avail to reduce physiology damage of airscrew. It also provides science foundation for safe design and manufacture of through-the-canopy-ejection-system.