Abstract: With AUTODYN-2D, the formative process of explosively formed projectile (EFP) with aluminum case is simulated. The influence of many factors including the thickness of shell and curvature of liner on the formation of EFP is studied, and the relationship of many structural parameters is obtained. Then the difference of shape of EFPs formed by the same structural warheads with aluminum case and steel case respectively are analysed. The simulation results would provide directive sense for the design of light weight EFP warheads.