Abstract: The Dionex DX-120 ion-chromatograph was used in the determination of F-,Cl-,NO-3 and SO2-4 anions in drinking water.The chromatographic conditions for separation of the four anions on the Dionex AS14 anion-separation column recommended and appendixed to the instrument was revised in this paper,making the analytical efficiency remarkably improved.Under the revised conditions,resolution of the peaks of the 4 anions achieved to values larger than 3.9.RSD′s of the results obtained were less than 2.5%.Recoveries found for the 4 anions were in the range of 94%-108%.In a comparative study for the accuracy of the results obtained by this method,as shown by the results of t-tests,no significant differences were founds as compared with the standard values and the results obtained by the chemical method of GB standard.