Abstract: OBJECTIVE To determine the genotoxic impurities of trifluoromethanesulfonate fludarabine by ion chromatography. METHODS The method was achieved on a C₁₈ column utilizing an eluent of0.15 mmol·L^-1 tetrabutylammonium hydroxide-0.090 mmol·L^-1 malic acid (pH 6.5)-acetonitrile (70:30) at a flow rate of 1.0 mL·min^-1 and the column temperature was 35℃, the detection method was direct conductivity detection. RESULTS This method could effectively determine the trifluoromethanesulfonate genotoxic impurities in fludarabine. The detection limit was 2.5 μg·mL^-1 and the limit of quantification was 7.4 μg·mL^-1, the linear range was 1.917-22.344 mg·L^-1, r=0.997 4. The method had good durability. CONCLUSION This method can effectively detect the genotoxic impurities of mesylate analogues. The method has high sensitivity, high accuracy and good durability.