Abstract: The sample is dissolved in nitric acid and potassium, the Cu, Zn and Ag are generated precipitatly ammino—compex and seperated from Fe, A1, Hg, Pb and Mn in the ammonia—ammonia water-ethyl solution.The content of silver at the solution is determinated with atomic absorption spectrophotometer method at 328.1 nm, sensitivity of the method is 0.033ug/mL, 1%absorption and detection limit is 0.024μg/mL.