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Al-Cu-Li alloy is a critical lightweight structural material in aviation and aerospace industry, which has become one of the key materials to manufacture the large aircraft structures in China. When the aircraft is in service in humid environments such as the ocean, it is vulnerable to be eroded by corrosive halide anions, and especially under the Cl^- ion erosion, its surface of Al-Cu-Li alloy components is prone to pitting corrosion, intergranular corrosion and exfoliation corrosion. The local corrosion of Al-Cu-Li alloy is mainly attributed to the potential difference between the alloy phase and the alloy matrix, which leads to the formation of micro-corrosion battery in the corrosive medium. The corrosion behavior of Al-Cu-Li alloy in NaCl solution and the effect of heat treatment on the corrosion resistance of the alloy were reviewed. The effects of coarse second phase particles and aging precipitates on the corrosion properties of Al-Cu-Li alloy were analyzed. In addition, the corrosion behavior in NaCl solution of different contents and electrochemical behavior in 3.5wt% NaCl solution of typical third generation Al-Cu-Li (2A97-T3, 2A97-T6, 2060-T8 and 2099-T83) alloys and conventional high strength aluminum alloy 2024-T4 used in aviation were studied in NaCl solution. The micro-corrosion morphology, corrosion electrochemical parameters and corrosion degree of each sample were analyzed. Finally, the corrosion resistance of each sample was obtained, from strong to weak in an order of: 2A97-T3>2A97-T6>2024-T4>2060-T8>2099-T83. Finally, the corrosion mechanism of Al-Cu-Li alloy in a corrosive medium was revealed, and the anti-corrosion measures of aluminum alloys in marine environments were summarized. This reseach progress provides reference for the subsequent development of the Al-Cu-Li alloy corrosion protection process and the enhancement in the corrosion resistance of aircraft in humid environments.