In the past, we evaluated the damage effectiveness of shrapnel pill without considering the dispersing blind area. Research and experiment show that dispersing dead area of shrapnel pill is in existence. In this paper, the math model of stochastic producing method of bullet falling point when taking into account the dispersing dead gone is set up, the damage effectiveness when considering dispersing blind area of shrapnel pill based on two representative target is analyzed, and through fixing other conditions, analyze different factor's influence on damage effectiveness. The calculated results show dispersing blind area affects the damage effectiveness of target greatly; controlling dispersing blind area radius rationally can improve the damage probability effectively.