OBJECTIVE：To e stablish UPLC characteristic chrom atograms of Euodia rutaecarpa ，processed E. rutaecarpa decoction piece ，water decoction and formula granules ，and to compare its relationship and difference. METHODS ：UPLC method was used. The determination was performed on YMC Triart C 18 column with mobile phase consisted of acetonitrile- 0.1％ phosphoric acid water solution （gradient elution ）at the flow rate of 0.3 mL/min. The detection wavelength was set at 254 nm，and column temperature was 30 ℃. The sample size was 1 μL. Using limonin as reference，the characteristic chromatograms of E. rutaecarpa ， processd E. rutaecarpa decoction piece ，water decoction and formula granules （each 10 batches，totally 60 batches）were drawn. The similarity was evaluated with TCM Chromatographic Fingerprint Similarity Evaluation System （2012 edition），and to determine the common characteristic peak. The differences of ratio of common characteristic peak area were evalucoted according to variance analysis. Meanwhile ，the cluster analysis and principal component analysis （PCA） were performed to research the differences of E. rutaecarpa ，processed E. rutaecarpa decoction piece ，water decoction and formula granules by using SPSS 20.0 software. RESULTS ：Totally 16 and 17 common peaks were respectively confirmed in characteristic chromatograms of E. rutaecarpa samples and processed E. rutaecarpa samples（decoction piece ，water decoction and formula granules ）. No. 8，9，11， 17 peaks were identified as limonin ，evodiamine，rutaecarpine and glycyrrhizic acid. Compared with decoction piece ，the similarities of characteristic peak between water decoction and formula granules were lower than 0.55，while those between water decoction and formula granule were higher than 0.95. Cluster analysis and PCA results showed that E. rutaecarpa decoction piece and processed E. rutaecarpa decoction piece could be clustered into one category ；E. rutaecarpa water decoction and formula granules could be clustered into one category ；processed E. rutaecarpa water decoction and formula granules could be clustered into one category. CONCLUSIONS ：Compared with E. rutaecarpa ，processed E. rutaecarpa additionally contain glycyrrhizic acid ； main che mical components of decoction piece ，water decoction and formula granules are basically the same ，but the contents of the components between decoction piece to water decoction and formula granules are different.