In order to acquire the influence of warhead shell materials on fragments forming,4 kinds of material,such as 82 steel, 50SiMnVB steel, 40CrMnSiB steel, 30CrMnSiNi2A steel, were studied to form fragments, using fragment warhead design software. The change laws of fragments scattering angle,initial velocity and mass distribution were obtained, and the fragment mass distribution was researched by experiment. It is found that,various alloy steels have similar almost the same influence on the fragments scattering angle and initial velocity, and have same diversification regular pattern along the warhead axial. Specially, the fragments scattering angle decreases at first and then increases, and its maximum initial velocity appears at the place about 72.5 % of warhead length. But various alloy steel has very different influences on fragmens mass distribution. With materials ultimate tensile strength increasing and fracture toughness decreasing, the warhead damage extent improves and total fragments number increases by 39.3%.