Abstract: The weldability of 7A05 aluminum alloy welded with two kinds of welding wires was investigated.Resultsindicated that the joints exhibit good anti-heat-cracking sensitivity and the tensile strength were ~75% that of the base metal. After postweld aging treatment, the tensile strength of joints was obviously increased. The smaller and the more the precipitated particles uniformly distributed on the grain boundary, the higher the tensile strength of the joint.