OBJECTIVE： To establish the method for the content determination of gentiopicrin and loganic acid in Gentiana scabra， and to investigate the correlation of their contents with appearance traits and quality gradation criterion. METHODS： HPLC method was adopted. The determination was performed on Ascentis Express C18 column with mobile phase consisted of 0.1％ phosphoric acid-acetonitrile （gradient elution） at the flow rate of 0.4 mL/min. The column temperature was 30 ℃， and detection wavelength was set at 240 nm. The sample size was 1 μL. Taking the length， number and diameter of fibrous roots as indexes， the appearance and morphological characteristics of G. scabra were studied. The relationship of gentiopicrin and loganic acid content with the appearance property of medicinal material was analyzed by SPSS 21.0 software. k-mean clustering analysis was carried out by using SPSS 21.0 software， and gradation standard for G. scabra was established preliminarily. RESULTS： The linear range of gentiopicrin and loganic acid were 0.5-3.0 μg/mL （r＝0.999 9） and 0.05-0.50 μg/mL （r＝0.999 9）. The limit of quantification of gentiopicrin and loganic acid were 0.295， 0.289 μg/mL； the detection limit were 0.082， 0.081 μg/mL； RSDs of precision， stability， repeatability tests were all lower than 2％； the recovery rates were 97.56％- 102.23％ （RSD＝1.56％， n＝6） and 97.58％-102.67％ （RSD＝1.86％， n＝6）. Correlation results showed that there was a significant positive correlation of the length of G. scabra， the number of roots， root diameter， with the contents of gentiopicrin and loganic acid. The order of affecting content was the number of roots ＞length ＞root diameter. k-means clustering analysis showed that 54 batches of G. scabra was divided into two categories； S4-S6，S13，S17-S23，S25，S28，S31-S34 were clustered into a category； S1-S3， S7-S12， S14-S16， S24， S26，S27，S29， S30，S35-S54 were clustered into the other category. The results of gradation showed that 54 batches of G. scabra could be divided into two grades， and the results were consistent with the cluster analysis. CONCLUSIONS： Established method is simple and stable， and can be used for simultaneous determination of gentiopicrin and loganic acid in G. scabra. The more fibrous roots， the longer the length， the thicker the root， the higher the content of gentiopicroside and loganic acid， the better the quality of G. scabra.