Abstract: Al-Cu-Mg-Ag aluminum alloy and ZL205A aluminum alloy are prepared by semi continuous casting. The flow properties, tensile properties at room and high temperatures, tensile fracture morphologies, intergranular corrosion depths and microstructures of the two alloys are compared and analyzed. The results show that when the pouring temperatures are 720℃ and 740℃, the flow properties of Al-Cu-Mg-Ag aluminum alloy are better than those of ZL205A aluminum alloy. At room temperature, 150℃, 200℃ and 250℃, the strengths of Al-Cu-Mg-Ag aluminum alloy are better than those of ZL205A aluminum alloy, and with the increase of temperature, the drop of strength of Al-Cu-Mg-Ag aluminum alloy is slighter than that of 205A aluminum alloy. The room temperature elongations of the two alloys are almost the same. The intergranular corrosion depth of Al-Cu-Mg-Ag aluminum alloy is in the range of 182-246 μm, lower than 274-337 μm of that of the ZL205A aluminum alloy. The width of precipitate free zone of Al-Cu-Mg-Ag aluminum alloy is narrower than that of ZL205A aluminum alloy.