Abstract: In accordance with the species indentification,and the determination of the physical and chemical properties and ages as well as the on-the-spot examination,it was found that the so called buried wood(jianchang board),a precious wood of Cunninghamia unicanaliculata Wang et Liu was buried under the ground for many years because of local earth crust changed.In the ground it had undergone changes in its chemical composition and therefore possessed a high resistance to rot. It is suggested that Dechang county area is the ancient natural distribution region of the species.