Traces of cadmium and bismuth in high-purity zinc metal were determined by inductively coupled plasma mass spectrometry (ICP-MS) in combination with flow injection (FI) on-line matrix separation (FI-ICP-MS). The anion-exchange separation method of the potassium iodide (KI) system was applied to the separation of the analytes from the matrix zinc. The analytes, cadmium and bismuth, were adsorbed on the anion-exchange (BIORAD AG1-X8) mini-column (1.0mm i.d. 100mm bed length), while the matrix zinc can be completely removed from the anion-exchange resin. The analytes were eluted by 2mol/l HNO3 and directly introduced into the ICP-MS. The detection limits (D.L.) obtained by using a single injection (350l) were 0.81 and 0.075ngg-1 for cadmium and bismuth, respectively. In the case of multi-injection concentration onto the anion-exchange mini-column (five injections 350l each), the detection limits could be improved to 0.16 and 0.014ngg-1 for cadmium and bismuth, respectively. The reproducibilities of the single injection and the multi-injection method were satisfactory with a relative standard deviation of less than 5% (at the 10 and 1ngml-1 level for the single injection and the multi-injection method, respectively). The method was successfully applied to the determination of trace impurities in four samples of high-purity zinc metal (7 nines grade) and three standard reference materials of high-purity unalloyed zinc samples (from NIST).