Objective To establish a HPLC-PDA method for the determination of baicalin, wogonoside, baicalein, wogonin and glycyrrhizic acid in Xiaochaihu Tang. Method A Symmetry Shield RP18 (4.6 mm x 250 mm, 5.0 microm) was used with a mobile phase of acetonitrile-0.01% H3PO4 in gradient elution. The detection wavelength was 251 nm,the flow rate was 0.45 mL x min(-1) and the column temperature was maintained at 30 degrees C. Result The accuracy, precision, sensitivity, specificity and linearity of this method met the requirements. The contents of the five effective fractions were determined simultaneously. Conclusion The method is rapid,simple and accurate and it can be suitable for the determination of baicalin, wogonoside, baicalein, wogonin and glycyrrhizic acid in Xiaochaihu Tang simultaneously.