Abstract: The effect of sensitization time on the microstructure and properties of domestic 8 mm-thick 5083-H116 aluminum alloy was studied. The results showed that with the increase of sensitization time, more and more beta phases precipitated on grain boundaries, forming a large number of network structures, the corrosion potential of the aluminum alloy decreased gradually, the intergranular corrosion tendency increasesd, the strength decreasesd, and the elongation increasesd.