The no.8 Grave at Chengyangcheng Site, located in Xinyang, Henan Province, is a noble tomb of Chu State during the late Warring States Period. More than 400 pieces of lacquer and wooden wares were excavated from the tomb, of which a lacquer-bamboo mat woven with black and red bamboo strips was the most exquisite. In order to understand the production process and to carry out the research on protection from dehydration of the painted bamboo mat, the composition and surface morphology of the bamboo mat lacquer film were analyzed using laser confocal microscopy, Raman spectrometry, Fourier infrared absorption spectrometry and scanning electron microscopy-energy dispersive spectrometry. The results show that the black color of bamboo mat lacquer film is the natural color of lacquer, and the red one is the color of lacquer mixed with vermilion. The surface of the black lacquer film is smooth and has a tight combination with the bamboo body, whereas the surface of red lacquer film is rough and its structure is loose. The lacquer film is between 0.02 and 0.03 mm thick, and is thought to have been formed by brushing with lacquer three to five times, based on simulated lacquer films.