Objective: To compare purification effect of Qingxiao oral liquid with membrane separation technology and alcohol precipitation method. Method: HPLC was adopted to determine the content of baicalin in Qingxiao oral liquid with mobile phase of methanol(A)-0.05% phosphoric acid solution(B) gradient elution(0-10 min

30%A;10-30 min

30%-50%A;30-45 min

50%-80%A) and detection wavelength at 280 nm

differences of dry extract yield

content and retention rate of baicalin between membrane separation samples and alcohol precipitation samples were investigated. Result: Retention rates of baicalin in membrane separation and alcohol precipitation samples were 92.01% and 72.79%

the amount of dry extract were 4.14 and 2.48 g

respectively. Conclusion: Retention rate of effective ingredient(baicalin) with membrane separation method was higher than alcohol precipitation method

but the latter had a better capacity by comparing with the former

appearance of samples had no significant difference in the observation period.