To reveal the different material bases of licorice from different regions,UPLC-TQ/MS was used to determine the content of 12 kinds nucleosides and nucleobase components in 153 batches of licorice from various producing regions,and principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA) were used to analysis the quality characteristics.The results showed that the content of nucleosides and nucleobase in licorice from different regions is:Ningxia >Gansu>Inner Mongolia>Xinjiang,and there has a significant difference (P<0.05).In nucleoside components,cytidine and guanosine had a higher content,and the total content of them accounted for 26.2%-47.8% of the total nucleoside and nucleobase content in licorice.In nucleobase content,adenine and guanine were higher,and the total content of them accounted for 19.3%-38.7% of the total nucleoside and nucleobase content in licorice.PLS-DA discrimination analysis could divide licorice from different regions into two groups based on the 12 kinds of nucleoside and nucleobase content.One is the licorice from Ningxia and Inner Mongolia,the other is from Gansu and Xinjiang.The main differential components were guanine,adenine,uridine,cytidine and guanosine.Further,the quality characteristics of licorice from different regions within the two groups were analyzed by PLS-DA,and the results showed that licorice from Gansu and Xinjiang can be clearly distinguished,while licorice from Ningxia and Inner Mongolia cannot be accurately distinguished.The above results illustrated that the nucleoside and nucleobase content in licorice from various regions was different,which will affect the quality characteristics.Based on nucleoside and nucleobase content,the quality of licorice from Ningxia and Inner Mongolia has a higher uniformity.This study provides theoretical support for revealing the differences in quality of licorice from different regions,and lays a foundation for its rational development and utilization.