Abstract: HG-AFS was applied to the determination of trace amounts of cadmium in environmental water.It was found that in 0.12 mol·L-1 HCl solution,cadmium(Ⅱ) was reacted with potassium borohydride solution (30 g·L-1) to form cadmium hydride and determined by AFS.Cobalt(Ⅱ) attaining to mass concentration of 1 mg·L-1 was added to the test solution to enhance the intensity of fluorescence signal,and 10 g·L-1 thiourea solution was added as complexing agent.Linear relationship between values of fluorescence intensity and mass concentration of cadmium(Ⅱ) was obtained in the range within 6.0 μg·L-1 with its detection limit (3s/k) of 0.18 μg·L-1.The proposed method was used in the analysis of a water sample,on the base of which recovery was tested by standard addition method,giving results of average recovery of 96.3% and 101.7%.