Abstract: For monitoring the acidity of precipitation more than forty observation stations had been established」in China and observations have been carried out during Mar. 1981 to Apr. 1983. A study of the data collected indicates that acid rain has already come into existence in a good part of southern China. The lowest pH-value in this region is found to be about 3.1,and the frequeney of presence is about 90%.Acid rain also occurs in Qingdao, Xi'an and Lushan. In this paper the distribution of these monitoring stations has been described and the influence of geographical environments, transport of pollutants and the relation to the activities of weather systems have also been discussed.