Abstract: To study the effect on mechanical properties of high solid loaded hydro reactive metal fuel propellant under compression, the uni-axial compression method and needle penetration determination were applied to studying the effects of metal content and gradation, binder content, and binding agent on mechanical properties of magnalium hydro reactive metal fuel propellant under room temperature. The results show that the metal roller effect exacerbates by metal content increasing, so that the mechanical declines; the migration phenomenon of the system liquid phase reduces with the binder content improving, which can improve the mechanical properties. Appropriate metal gradation and bonding agent can improve the mechanical properties.