OBJECTIVE:To establish the RP-HPLC method for determination of ginsenoside Rg1 in Aidi injection. METHODS:The determination was performed on Lichrospher C18(250 mm?4.6 mm,5 ?m) with column temperature kept at 35 ℃. The mobile phase consisted of water -acetonitrile (gradient elution) at a flow rate of 1.0 mL?min-1.The detection wavelength was set at 203 nm. RESULTS:The linear range of ginsenoside Rg1 was 5.0～250.0 ?g?mL-1(r=0.999 5),and the average recovery was 97.43%(RSD=1.81%,n=6). CONCLUSION:The method is simple,rapid and accurate,and it is suitable for the quality control of Aidi injection.