Abstract The effects of aging on the microstructure, mechanical properties, intergranular corrosion, and exfoliation corrosion of an Al-3.5Cu-1.5Li-0.22(Sc+Zr) alloy have been investigated. The results show that the alloy has the character of age hardening, and the major phase of precipitation and strengthening is the T 1 phase. The aging temperature and aging time have a significant effect on the amount and distribution of the T 1 phase. The proper artificial single-aging treatment of the alloy is at 160r°C for 40 h. The intergranular corrosion and exfoliation corrosion of the alloy are caused by the anodic dissolution of the T 1 phase and the precipitate-free zone (PFZ). With increasing the aging time to overaged, the T 1 phase coarsens, and the PFZ widens, leading to an increase in the susceptibility to intergranular corrosion and exfoliation corrosion.