Abstract: To establish a RP-HPLC method for the determination of content of sisomicin sulfate and sodium chloride injection. Thermo Aminoglycoside RP 18(4. 6 mm ×150 mm, 3 μm)column was used. The mobile phase consisted of Sodium heptane sulfonate solution(take 6 g of sodium heptane sulfonate, add 0. 1 mol/L potassium dihydrogen phosphate solution and dilute to 1 000 mL, adjust the pH to 1. 5 with phosphoric acid)- acetonitrile(77∶23). The detection wavelength was 205 nm, the flow rate was 1. 0 mL/min. and the column temperature was 35 °C. The separation of sisomicin peaks with related substances and the degradation products was good. The linear range of the peak area with sisomicin was 0. 010 024-1. 002 4 mg/mL(Y=4. 210 2×10⁶ X+9. 107 0×10³, r=0. 999 9, n=7), the detection limit was 0. 6 ng, the limit of quantification was 2 ng, and the recovery rate was at 99. 1%-100. 9%(RSD< 1. 0%, n=9). The method is sensitive, exclusive, accurate and suitable for the determination of sisomicin. Compared with the antibiotic microbiological test method, the specificity is better, the confidence interval of the result is narrowed, and the test time is saved.