OBJECTIVE: To establish a method for the content determination of paeoniflorin in Bazhen pill (concentrated pill). METHODS: HPLC was performed on the column of wondasil C18 with mobile phase of acetonitrile -1% phosphoric acid (15 ∶ 85, V/V) at a flow rate of 1.0 ml/min, the detection wavelength was 230 nm, and column temperature was 30 ℃. RESULTS: The linear range of paeoniflorin was 0219-1.32 μg(r=0.999 9); RSDs of precision, stability and reproducibility tests were lower than 1%; recovery was 95.82%-101.82% (RSD=2.13%,n=6). CONCLUSIONS: The method is simple, stable and reproducible, and can be used for the content determination of Bazhen pill (concentrated pill).