Compared to modern counterparts,studies have been done on the wood changes of chemical components and structure of the waterlogged uncovered from Changtaiguan Tomb No.7.Some suggestions on preservation of ancient waterlogged wood have been provided.The results indicate that the waterlogged coffin wood from Changtaiguan may be eroded heavily.Compared with modern fresh wood,contents of hot water extractives and organic extractives in ancient wood have decreased,and contents of holocellulose and pentosan have declined sharply,while contents of lignin and ash have relatively increased.Sulfur content in the ancient wood is approximately the same as the modern fresh one and iron content in the ancient wood is much richer than the modern fresh one.Treatments using PEG or and sugars are unsuitable for the waterlogged coffin wood uncovered from No.7 Ancient Tomb in Changtaiguan.