OBJECTIVE：To establish HP LC ch aracteristic ch romatogram of different medicinal parts of Cirsium japonicum ， and to compare the difference of chemical components in different medicinal parts of C. japonicum according to chemical identification method ，and to provide reference for quality control and evaluation of C. japonicum . METHODS ：Medicinal material （overground part ），leaves，flower，main stem and lateral stem of C. japonicum were determined by HPLC. According to the TCM Chromatographic Fingerprint Similarity Evaluation System （2012A edition ），the chromatograms were matched to generate the HPLC characteristic chromatogram of each medicinal part. The differences of common characteristic peak area were analyzed according to variance analysis of single factor. The chromatographic peaks were identified by comparison of reference substance. Meanwhile，the chemical pattern recognition was performed to research the different medicinal parts of C. japonicum according to principal component analysis （PCA）and cluster analysis. RESULTS ：HPLC characteristic chromatograms of medicinal material ， leaves，flower，main stem and lateral stem from C. japonicum were established respectively ，and 15 common peaks were confirmed for medicinal material ，leaves and flower of C. japonicum ；11 common peaks were confirmed in chromatograms of main stem and lateral stem from C. japonicum （absence of No. 7，9，12，13 peak）. The contents of chemical components were different greatly among different medicinal parts. No. 1，2，3，10，11 peaks were identified as neochlorogenic acid ，chlorogenic acid ， cryptochlorogenic acid ，linarin and pectolinarin. Results of PCA and cluster analysis showed that chemical pattern recognition and clustering of the flower and stem of C. japonicum were distinct and can be clustered into one category respectively. However ，the leaves distribution of C. japonicum was relatively scattered ，so it was difficult to cluster . CONCLUSIONS ：Established HPLC characteristic chromatogram-chemical pattern recognition can reflect the differences of different medicinal parts of C. japonicum integrally， comprehensively and truly ， which has vital significance for origin indentification ， quality control and overall evaluation of C. japonicum .