Protein materials were usually used as binding media in wall paintings and colored relics of ancient architecture,and therefore their aging and deterioration may cause fading and peelingoff of pigments.The relative content of binding media is closely related to the decay of this type of cultural heritage.Therefore,quantitative analysis of proteins is very important for the study of decay mechanisms,restoration and conservation of painted cultural heritage objects.This article summarizes the methods used for analysis of protein content,including the Kjeldahl method and spectrophotometry. Methods used,for example,gas chromatographymass spectrometry（GCMS）,amino acid analysis and elemental analysis,to analyze the protein content in pigment layers of colored relics and in plaster layers of wall paintings in ancient architectures are highlighted.The principles,characteristics and applications of these methods are also introduced.From the results obtained,it seems that all the methods mentioned play very important roles in the analysis of protein content in colorants used in polychrome relics and ancient architectural plaster.