Most of the Tibetan wall paintings are brushed with a protective coating on their surface. According to the literature, the coating materials are mainly tung oil, animal glue and varnish. But until now, little scientific research on these materials has been reported, which is not helpful for the conservation and restoration of Tibetan wall paintings. In this article, coating samples obtained from the surface of wall paintings in Labrang Temple were analyzed by Fourier transform infrared spectroscopy, ¹Hnuclear magnetic resonance and Pyrolysisgas chromatographymass spectrometry. The results indicated that the material for the coating of wall paintings in Labrang Temple was a kind of drying oil similar to tung oil. The materials and techniques employed in the making of Tibetan wall paintings, as well as ageing and coating of wall paintings in Labrang Temple made it more complicated and suggested different properties from the modern tung oil.For conservation and restoration, drying oils with properties closer to the traditional Tibetan coating materials, e.g.tung oil, could be used as a conservation material for the coating of wall paintings in Labrang Temple.