In order to explore whether AgI will pollute the environment after seeding, snow water sample data were collected in the snow enhancement experiment by using a ground AgI generator from December 2002 to March 2003 at Jianzishan Mountain of Beijing. Ag+ concentration and other chemistry components in the snow water are analyzed. The results show that Ag+ concentration varied obviously under different weather patterns. There is no direct linear relation between Ag+ concentration change and catalyst amount. The Ag+ concentration in the snow is far below the drinking water standards of China. There are obvious chemical char acteristics in the snow water: the concentrations of SO2-4 and NO-3 are the highest in the anions, and the concentrations of Ca2+ and NH+4 are the highest in the cations. The total ion concentration in the snow water is much lower than that of the heavily polluted fog water observed in the Beijing area.