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Acid rain is natural precipitation with a pH value of less than 5.6. The formation of acid rain is a complex atmospheric chemical and physical phenomenon. Acid rain contains various inorganic and organic acids, such as sulfuric acid and nitric acid, with sulfuric acid being the predominant component in most cases. The formation of acid rain is closely related to human industrial activities. Sulfuric acid and nitric acid are produced artificially from sulfur dioxide and nitrogen oxides, which can be emitted locally or transported from distant areas. Sulfur dioxide accounts for 60%–70% of global acid deposition. Existing studies have shown that both are converted into sulfuric acid and nitric acid through homogeneous oxidation and heterogeneous oxidation in the atmosphere. With societal progress and industrial development, the area and volume of acid rain deposition have **increased**, leading to serious problems and having a significant impact on ecosystems. In most areas south of the Yangtze River, the average pH value of precipitation is below 4.5, making them severely affected areas by acid rain in China. The problem of acid rain has become one of the main factors hindering the sustainable economic development of our country. The effects of acid deposition lead to forest degradation and the acidification of surface waters, as well as significant reductions in the yield of vegetables, fruits, and grains. Acid rain also causes damage to buildings and bridges due to corrosion, resulting in the distortion of historical monuments. Acid rain also releases heavy metals such as aluminum, cadmium, lead, and mercury from the soil, which enter the human body through food and fish, posing a threat to human health.