Abstract:3%~5% Ni element is added to the Al-Zn-Mg-Cu deformed aluminum alloy, and a large amount of Al3Ni phases are formed by eutectic reaction, the particle strengthening effect of the Al3Ni phases is added besides of MgZn2 aging strengthening. The increase of Ni content not only improves the casting performance and weldability of the Al-Zn-Mg-Cu deformed aluminum alloy, but also increases the tensile strength and yield strength. The preferred composition of Al-Zn-Ni-Mg-Cu aluminum alloy is Al-5.6Zn-3.5Ni-2Mg-1Cu. Its tensile strength, yield strength and elongation are 650MPa, 572MPa and 7.5%, respectively. The tensile strength and elongation of its welded joint were 323 MPa and 2%, respectively. With the increase of Zn content, the Al3Ni phase changes from interfacial tear to self-fracture. Increasing the content of Ni helps to increase the strengthening effect of Al3Ni phases, but the content of Ni cannot beyond the eutectic point.Decreasing the aspect ratio of Al3Ni particles helps to suppress the self-fracture of Al3Ni phases. Uniform distribution of Al3Ni phase helps to prevent the abnormal growing of recrystallized grains.