Abstract: This article is developed to describe the whole process of "∫" growth of woody plants——Power-exponential equation of growth:S=ce-^Bt-A This equation is different from the general model of the simulating growth, it is infered from the theory of growth described below: with rest conditions equal the absolute growth rate (dW/dt) of the weight of the plant body is directly proportional to the weight of the original plant body (Ⅳ), and inversely proportional to the decrepitness (t^α). Hence mathematic expressions of the absolute growth rate, the relative growth rate and the fastest growing time are derived therefrom.It has been proved that this model is of a higher goodness of fit, the index of correlation ordinarily can reach above 0.99, by using that equation to fit pratical data, and compare with some models of growth. It can be used for gorwth projection and construction of yield table. Theoretically, it may be valuable to interpolation of missing data, and searcting the way of plants growing mechanism etc.