Abstract: The elemental composition and chemical states of the surface film of silver-electroplated deposits with different treatment and aging time have been investigated by means of XPS and AES. The results showed: ( 1 ) Fresh deposit U0, stored indoors in a transparent desiccator for 5 days, was composed of the elements silver, oxygen, sulphur, chlorine and the matrix metal copper in addition to contaminating elements carbon, potassium and nitrogen; the content of elemental silver of a series of untarished deposits U0 and U1 decreased steadily with time, while elemental oxygen increased almost linearly. ( 2 ) The distributions of the elements silver and oxygen of deposit U1, treated with NaCl solution, were the same in Auger line scan, but for deposit U2, treated with Na2S solution, the coexistence regions of the elements silver and sulphur partly replaced those of silver and oxygen.The atomic ratio of S/Ag differed with the treatment of the silver deposit. The ratios for deposit U3, stored indoors in a transparent desiccator for 500 days, and for deposit Ts,stored indoors in a transparent desiccator containing air with 1% H2S for 24 hours, were much greater than that for deposit T1 which is exposed to sunlight outdoors for 24 hours. ( 3 ) The two dimensional Auger parameter plot showed that Ag2O amounted to 19% of the total silver in deposit T1, and was practically nil in deposit U0. (4) The anti-tarishing ability of fresh deposit increased markedly after treatment with certain reducing or complexing agents. Based on these results, the tarnishing mechanism and anti-tarishing principle were discussed.