Abstract: A two-stage solution and aging treatment was conducted on 7A04 aluminum alloy, and then the effects of solution temperature and time on the microstructure and mechanical properties of the alloy were investigated by the orthogonal experiment. The optimal two-stage solution process was obtained. The results show that the optimal two-stage solution process was determined as: 450 ℃×30 min+505 ℃×60 min. Under this optimal process and followed by aging at 120 ℃ for 24 h, the tensile strength, yield strength, elongation and impact energy of the aluminum alloy reached 658.43 MPa, 593.07 MPa, 10.25% and 9.681 J, respectively. The first stage solution is the main influence factor on the mechanical properties of 7A04 aluminum alloy. However, the second stage solution at a relatively high temperature can remarkably improve the dissolution of the second phase, eutectic inclusions and intermetallic compounds, which precipitate as strengthening phases during the following aging treatment, and then results in the improvement of comprehensive performance of the alloy.