Abstract: The differential analysis of different P.lactiflora varieties was carried out based on metabolomics.Methanol vortex method was used to extract secondary metabolites, ultra-performance liquid chromatography-tandem mass spectrometry（UPLC-MS/MS） was used to separate and identify the components, and original data were screened based on the Metware Database.Quality control analysis, principal component analysis, orthogonal partial least squares discriminant analysis（OPLS-DA）,cluster analysis and repeated correlation evaluation were carried out for the metabolites of different varieties of peony.The difference of secondary metabolites among three P.lactiflora varieties were studied, in order to provide reference for application, cultivation and genetic improvement of peony.The results showed that 464 kinds of secondary metabolites included terpenoids, alkaloids, phenolic acids, tannins, lignin and coumarins were identified from the three P.lactiflora varieties.Principal component analysis and partial least square discriminant analysis showed that there were significant differences in secondary metabolites among the three peony varieties.A total of 53 metabolites with significant difference among 3 varieties were obtained（up-regulated 26,down-regulated 27）.A total of 194 differential metabolic pathways were obtained by using KEGG database annotation, in which were enriched to secondary metabolism product biosynthesis pathway, phenylalanine metabolism, niacin and nicotinamide metabolism, glycolytic metabolism and benzoxazine biosynthesis, a total of 5 biosynthetic pathways.This study showed that there were significant differences in the types and contents of secondary metabolites among ‘Red Charm’‘Dafugui’ and ‘Fanyunu’,indicated that the secondary metabolites of the three P.lactiflora varieties were significantly different, among which ‘Fenyunu’ was suitable for medicinal use and ‘Dafugui’ was suitable for ornamental.The differentially expressed procyanidins and the products of phenylalanine metabolism may be related to the differences in flower color among the three varieties.These results laid a good foundation for further research on the medicinal value, cultivation breeding and genetic improvement of P.lactiflora.