Objective: To establish a method for determining the content of oleanolic acid in the fruit of Acanthopanax sessiliflorus. Method: Microwave digestion procedure was applied for digesting the glycosides of oleanolic acid. HPLC was used for determining the content. A Promosil C18 column (4.6 mm×250 mm

5 μm) was used with a mobile phase of methanol-0.2% acetic acid (90:10). The flow rate was set at 1.0 mL·min-1. The UV detection wavelength was set at 210 nm. Result: The fruits were digested with 9% HCl at 0.1 MPa for 0.5 h;the liner range of oleanolic acid was 0.781 6-3.908 μg(r=0.999 6). The average recovery of oleanolic acid was 97.3% (RSD 1.2%). Conclusion: The method is accurate and reliable and can be used for the quality control of the fruits of A. sessiliflorus.