Galvanized steel is a cost-effective and corrosion-resistant material with high strength, making it a popular choice for various engineering applications. In order to investigate the effects of ambient temperature and galvanized layer state on the corrosion of galvanized steel in a high-humidity neutral atmosphere environment, we placed three types of specimens (Q235 steel, undamaged galvanized steel, damaged galvanized steel) in a neutral atmosphere environment with a humidity of 95% at three different temperatures (50 °C, 70 °C, and 90 °C) for testing. The corrosion behavior of specimens under simulated high-temperature and high-humidity conditions was studied using weight changes, macroscopic and microscopic observations, and analysis of the corrosion products of the specimens before and after corrosion. Emphasis was placed on examining the effects of temperature and damage to the galvanized layer on the corrosion rate of the specimens. The findings indicated that damaged galvanized steel retains good corrosion resistance at 50 °C. However, at 70 °C and 90 °C, the damage to the galvanized layer will accelerate the corrosion of the base metal.