In order to provide a reference for optimal grenade design,FLUENT simulation software was applied to study the effect of smallcaliber subsonic warhead’s fuze shape on aerodynamic characteristics of grenades,drag coefficient lift coefficient,pitching moment coefficients and center of pressure variation of three grenades’ head shapes（ singe cone,truncated combination and hemispherical） at different angles of attack,different Mach number were achieved. The results show that： angle of attack has no obvious effect on the drag coefficient lift coefficient. When Mach number is less than 0. 7,drag coefficient of grenade with the hemispherical head shape is minimum,its lift coefficient is maximum; when Mach number is greater than 0. 7,drag coefficient of grenade with truncated combination head shape is minimum,its lift coefficient is maximum.