OBJECTIVE：To establish a method for simultaneous determination of 12 components including naringin ， hesperidin，neohesperidin，aloe emodin ，rhein，notopterol，emodin，honokiol，isoimperatorin，magnolol，chrysophanol and physcion in classical formula Sanhua tang. METHODS ： HPLC-multi-wavelength switching technology was adopted. The determination was performed on COSMOSIL C 18 with mobile phase consisted of acetonitrile- 0.1％ phosphoric acid （gradient elution）at the flow rate of 1.0 mL/min. The detection wavelength was 280 nm（naringin，hesperidin，neohesperidin），254 nm （aloe emodin ，rhein，chrysophanol，emodin methyl ether ），310 nm（notopterol，emodin，honokiol，isoimperatorin，magnolol）. The column temperature was set at 30 ℃，and the sample size was 10 μL. RESULTS：A total of 12 components were well separated without negative interference. The linear range of naringin ，hesperidin，neohesperidin，aloe emodin ，rhein，notopterol， emodin，honokiol，isoimperatorin，magnolol，chrysophanol and physcion were 55.4-5 540，3.8-380，45.6-4 560，1.2-120， 2.1-210，2.2-220，2-200，2.4-240，0.8-80，1.2-120，1.7-170，1.1-110 μg/mL（R 2≥0.999 6），respectively. The detection limits were 0.064，0.024，0.053，0.018，0.020，0.041，0.050，0.091，0.030，0.180，0.028 and 0.083 μg/mL，respectively. The limits of quantitation were 0.213，0.075，0.174，0.060，0.063，0.138， 0.166，0.323，0.130，0.600，0.094 and 0.275 μ g/mL，respec- 9721004） tively. RSDs of precision ，stability （24 h） and repeatability 2633531778@qq.com tests were all lower than 2％（n＝6）. Average recoveries were 99.54％，99.69％，100.01％，99.93％，100.36％，99.65％， 100.03％，100.47％，99.97％，100.68％，99.90％，100.17％ （all RSDs were lower than 2％，n＝6），respectively. CONCLUSIONS ：Established HPLC-multi- wavelength switching technology is simple ，specific and stable ，which could be used for the simultaneous determination of 12 components in Sanhua tang as naringin，hesperidin，neohesperidin.