Abstract: A study on the composition and morphology of the corrosion layer on H59 brass and 2024, 5052 aluminum alloy samples exposed to natural conditions for 1 and 3 years in Anhui Province was conduceted, and the atmospheric corrosion mechanism of the alloys was also explored. Using the corrosion loss method, the corrosion rate of the sample was obtain, the atmospheric corrosion level was evaluated, and the influence of major environmental factors on the atmospheric corrosion rate of copper and aluminum alloy samples was revealed with grey correlation analysis. The results indicate that H59 brass exhibited zinc removal corrosion, and the corrosion layer provided weak protection to the substrate. The atmospheric corrosion level was between C2 and C3, 2024 and 5052 aluminum alloys first experienced pitting corrosion, which then developed into full-scale corrosion. The degree of corrosion was much lower than that of H59 brass, and the atmospheric corrosion level was mostly C1 and C2. H59 brass's atmospheric corrosion was greatly affected by the atmospheric environment. Grey correlation analysis shows that temperature and humidity had the greatest impact, PM2.5 and PM10 particles had the smallest impact, and SO₂ had a small impact.