Abstract: In order to investigate the influence of domestic 5356 welding wire on the properties of 6061 aluminum alloy after post-weld heat treatment, inert gas shielded welding (MIG) was used for welding. The samples were prepared through solution treatment and solution treatment + aging. The welding area was characterized by microhardness tester, tensile testing machine and scanning electron microscope (SEM). The results show that after solution treatment + aging heat treatment, the hardness of the heat-affected zone reaches 110HV, the strength of the welded joint increases by 18.6%, and the elongation decreases by 25%.