To realize the nondestructive discriminant analysis of the pigments used in polychrome relics，the diffuse reflectance spectra for 12 kinds of pigments reference samples were collected.According to the shapes of the spectra，the reference samples were divided into two categories:red yellow and blue green.Principal component analysis(PCA) was used to reduce the dimensions of the spectra data sets of the two kinds of reference samples，and three principal components were extracted.The difference between the pigments was confirmed by using the scatter plot of PCA，and the spectral wavelength range with the highest contribution to the difference was discussed with the components matrix.Based on the PCA analysis results，the linear discriminant analysis(LDA) was used to fit the discriminant function which was applied in the analysis of two paintings samples from Renshou Hall of the Summer Palace.According to the distance between the scatter diagram of sample score discrimination and the reference samples of each category，the pigments used for cultural relics were determined to be hematite and ultramarine，respectively.Results showed that the discriminant function could be used to distinguish the kinds of pigments accurately，and analyze and identify the cultural relics pigments nondestructively.Nevertheless，the pollution or aging of cultural relics samples may affect the analysis，the surface cleaning is thus required in advance.