OBJECTIVE：Compare the fingerprint difference of Vaccariae Semen before and after processed （stir-fried），and to determine the contents of erythrine and vaccarin before and after stir-fried. METHODS ：UPLC method was adopted. The determination was performed on YMC Trait C 18 column with mobile phase consisted of acetonitrile-water （gradient elution ）at the flow rate of 0.35 mL/min. The detection wavelength was set at 219 nm，and the column temperature was 35 ℃. The sample size was 1 μL. Using vaccarin as reference，the fingerprints of Vaccariae Semen crude product and its processed product （each of 17 batches，S1-S17，CS18-CS34） were drawn. The similarity evaluation and common peak identification were carried out by Similarity Evaluation System of TCM Chromatographic Fingerprint （2012 edition）；cluster analysis ，principle component analysis （PCA）and factor analysis were performed by using SPSS 20.0 software. The contents of erythrine and vaccarin in Vaccariae Semen crude product and its processed product were determined by UPLC. RESULTS ：There were 5 common peaks in UPLC fingerprints of 17 batches of Vaccariae Semen crude product and its processed product. The similarities were all higher than 0.99. Among them ， 2 common peaks were identified ，i.e. erythrine ，vaccarin. Results of cluster analysis showed that S 1-S17 were clustered into one category and CS 18-CS34 were clustered into one category. Results of PCA and factor analysis showed that variance contribution rate of the first principle component was 76.418％；erythrine and vaccarin had higher loading on the first principal component （eigenvalues were 0.976 and 0.966，respectively）. The linear ranges of above 2 components were 6.437-321.832 μg/mL and 7.729-386.437 μg/mL，respectively（r＞0.999）. The limits of detection and quantitation were 0.085，0.284 ng （crude product） and 0.739， 2.465 ng （processed product ）， respectively. RSDs of precision ，reproducibility，stability（12 h）and durability tests were all lower than 3％（n＝6 or n＝5）. E-mail：1083656123@qq.com Average recoveries were 96.42％（RSD＝0.85％，n＝6）and 99.13％（RSD＝1.74％，n＝6）. The contents of the two components were 0.11％-0.20％，0.42％-0.63％（crude product ）and 0.08％-0.11％，0.34％-0.50％（processed product ）. CONCLUSIONS ：UPLC fingerprint of Vaccariae Semen crude product and its processed product are established successfully. Although the chemical constituents in Vaccariae Semen are consistent before and after stir-fried ，the contents of erythrine and vaccarin are all decreased after stir-fried.