Abstract: Experiment was conducted on determination of stress wave in a living Cinnamomum camphora tree and one disk with different moisture content. The results showed that the stress wave velocity in tree was inversely proportional to moisture content. When the moisture content of tree was lower than the saturation point of wood, the internal wave velocity was more obviously affected by the moisture content. When the moisture content of tree was above the saturation point of wood, the decreasing trend of wave velocity slowed down. The experiment resulted that the wave velocity, direction angle, moisture content and tree species satisfied the function relation of ??=1+????2+mc·T , and coefficient of determination was higher than 0.93.