Abstract: The aim of this study was to investigate the effects of different drying methods on the contents of monoterpene glycosides and phenolic acids in Paeoniae Radix Alba,and to provide a scientific basis for the selection of appropriate drying method for Paeoniae Radix Alba.HPLC was used to simultaneously determine the contents of 4 monoterpene glycosides and 2 phenolic acids with different drying methods.Principal component analysis (PCA) was carried out by SPSS software to evaluate the quality of different processed products from Paeoniae Radix Alba.The results showed that the contents of chemical components and water content were in accordance with the requirements of Chinese Pharmacopoeia (Version 2015).The highest total contents of monoterpene glycosides and phenolic acids in Paeoniae Radix Alba processed by vacuum freeze drying were 6.248% and followed by processed by drying with hot air at 60 ℃ (6.141%).According to the PCA results,the comprehensive scores of monoterpene glycoside and phenolic acid compounds in Paeoniae Radix Alba processed with different drying methods in the order from high to low were vacuum freeze dried > dried with hot air at 60 ℃ > microwave dried > far infrared dried > sun dried > dried with hot air at 40 ℃ > dried with hot air at 80 ℃ > shade dried > dried with hot air at 100 ℃.In conclusion,different drying methods had certain effects on the content monoterpene glycoside and phenolic acid compounds in Paeoniae Radix Alba.Drying with hot air at 60 ℃ was the appropriate drying method of Paeoniae Radix Alba by comprehensive analysis of the content,cost and practicality.

Key words: Paeoniae Radix Alba, drying method, HPLC, PCA evaluation