The invention discloses a low density impact resistant metal material which comprises the following materials by weight: 1.5-3.1% of C, 1.2-1.9% ofSi, 1.69-2.32% of Mn, 0.033-0.042%of S, 0.021-0.025% of P, 1.8-3.6% of Cr, 1.6-3.6% of Ni, 1.56-2.25% of Mo, 0.45-0.68% of Co, 0.63-1.18% of Fe, and balance of Cu. The low density impact resistant metal material has the quality characteristics of strong mechanical properties, good plasticity and low density and the like. Through addition of a small amount of 1.6-3.6% of Ni, 1.56-2.25% of Mo, 0.45-0.68% of Co and 0.63-1.18% of Fe, the metal material self density is reduced further, the metal material quality is effectively guaranteed, by once casting forming, quenching or nitriding is not needed, the antiwear and impact resistant ability can be improved, at the same time, the processing time is saved, the manufacturing cost is reduced, and the production efficiency is increased.