Abstract: Researches of the chemical characteristics of fog-water developed rapidly in China since 1980. Observation, sampling and analysis have been done in the cities, on the alps and by the seas. Studies of the acidity of cloud-fog water and the source of acid fog at each place have been done. The basic characteristics of fog water chemical composition also been detected. In many compositive fog observations, there explored the related factors of fog-water chemical characteristics from the continuous fogwater collection, and studied the primary factors which affect the concentration of the fog water chemical composition. The paper summarized the main studies of fog-water chemical characteristics in China during the last 30 years. Fogwater sampling and analysis have made marked progress. The cloudfog water chemical composition and acidity were confirmed in many cities and mountain areas. Many efficacious works have been done about the source of the chemical composition. The studies show that the cloudfog water in many of Chinese cities and mountain areas have been acidified. Fogwater was polluted with high ion concentrations, which would jeopardize people’s health. As a result, it’s very urgent to control pollutant discharge, raise the vegetation cover rate, and improve ecological environment.