Objective: To develop a method for simultaneous determining p-coumaric acid and cinnamic acid contents in Scutellaria barbata. Method: Eclipse SB-C18column (4.6 mm×250 mm

5 μm) was adopted with a mobile phase of acetonitrile-0.2% phosphoric acid at the flow rate of 1.0 mL·min-1. The detection wavelength was set at 310 nm and 280 nm and the column temperature was 26℃. Result: The good linear range was 0.148-1.776 μg (r=0.9998) for p-coumaric acid and 0.062-0.992 μg (r=0.9996) for cinnamic acid. The average recovery rate was 99.4%(RSD 1.5%) and 99.3%(RSD 1.8%) for p-coumaric acid and cinnamic acid respectively. The sample solution was steady within 12 h. Through the determination of the 8 batches of S. barbata

results showed that the contents of these 2 components in Hubei samples (batch number:130501) were better than those of other areas. Conclusion: This method is precise and accurate for determination of p-coumaric acid and cinnamic acid contents in S. barbata.