Rainwater is an essential pathway to remove fine particulate matter and dissolved atmospheric pollutants (e.g., SO 2 , HNO 3 , and NH 3 ). Acid rain (pH < 5.6) has been a severe environmental issue in China since the 1970s, adversely impacting ecosystem health. This study focuses on the influence of anthropogenically induced anions (SO 4 2– and NO 3 – ) and alkaline cations (Ca 2+ and NH 4 + ) on acid rain in Chinese cities. In this review, cities with high population density east of the Hu Huanyong Line that divides China geographically according to its uneven economic development were studied. Coastal and central areas of China to the east of the line are characterized by a much faster developing economy and rapid urbanization. The observed trends and spatial variability of acidity and chemical composition in rainwater are discussed in relation to industrialization and environmental changes in China. Over the past 3½ decades, the precipitation pH in the urban regions has exhibited reduced acidity. A mixed nitric–sulfuric acid rain type has become prominent due to the significant decrease in SO 4 2– via desulfurization. Ca 2+ levels have decreased, while NH 4 + has increased slightly due to more vehicular transportation. In addition, the neutralization capacity of Ca 2+ and NH 4 + has decreased from north to south. Overall, the acid rain problem in Chinese cities has been alleviated in recent years.