OBJECTIVE： To establish a method for the content determination of baicalin in Yangyin mixture. METHODS： HPLC was performed on the column of SunFire C18 with mobile phase of methnol-water-phosphoric acid （43 ∶ 57 ∶ 0.2，V/V/V） at a flow rate of 1.0 ml/min， the detection wavelength was 280 nm，  column temperature was 30 ℃， and the volume injection was 10 μl. RESULTS： The linear range of baicalin was 0.055 75-1.115 μg（r＝0.999 9）； RSDs of precision， stability and reproducibility test were lower than 2％； recovery was 95.39％-98.44％ （RSD＝1.19％，n＝6）. CONCLUSIONS： The method is simple， rapid and accurate， and suitable for the content determination of baicalin in Yangyin mixture.