Abstract: Rational management density was one of the key techniques to realize directive breeding of poplar and brich natural forests, which help to improve the stability and economic benefit of forests. In order to discuss the effects of different management density on the growth, fixed sample plots were set up respectively with the different density under the dif ferent stand types and site conditions. The characters (height, diameter, volume and etc), form quality index, utility rate of luminous energy, nutrient and the moisture change of the soil were observed continuously. On the base of site classification of poplar and brich natural forests, we analyzed quantitatively the effects of different management density on utility rate of luminous energy, content of nutrition return, content of containing water of woodland soil, growth of the forest as well as the effect of timber quantity. The result showed that the management density obviously affected the growth of forests, accumulating of dry matter, litter fall decomposing, and the improvement of soil structure. The individual leaf content reduced along with the management density increasing. The total area of individual leaf and average crown of stand were maximal in the medium management density. The decomposing rate of litter fall decreased along with the density increasing. The returns of nutritive element were the most in medium management density. The moisture content of different depth soil reduced along with the depth deepening in the same density. The moisture reduced along with the density descending in the same depth. The annual growth of diameter of unit area increased along with the density descending of the polar and brich forests. The stand accumulation was the most in the medium management density.