In order to study the deterioration of the polychrome potteries excavated from Chu (one of the states in the Warring States Period) tombs of the Chengyangcheng Site in Xinyang, Henan, we used X-ray fluorescence (XRF), infrared (IR) and Raman spectrometry to analyze mineral pigments of the pottery surfaces and metal coatings. The results show that this batch of potteries belongs to typical northern type, having high silica but low alumina, high water absorption rates, relatively looser structures, and firing temperatures ranging from 930℃ to 1025℃. The red pigments of the pottery surfaces are mainly cinnabar and hematite, and the yellow ones are goethite. The metal coatings of some painted potteries from Tomb No.8 contain tin (Sn). This research could provide a scientific basis for cultural relic conservation and restoration in the future.