A HPLC was established to determine osthol in Gujin pills.Phenomenex (250 nm×4.6 mm) was used, mobile phase was acetonitrile-water (60:40), flow rate was 1 mL/min, detection wavelength was 322 nm, injection volume was 20 μl, and column temperature was 30°C.Osthol had good linear relationship within range of 1.308-3.488 μg (r=0.9997), average recovery rate was 97.53% and RSD was 1.93% (n=6).The method was simple, accurate and with good repeatability, and it could be used in quality control of Gujin pills.