Abstract:In every organism of paulownia tree,nutrient element concents is the highest in flowers and leaves,the least in the trunk.Leaves and branches are the storehouse of nitrogen,the contents of nitrogen in the leaf account for 42—45 percent of the total of a tree.Root is the storehouse of phosphorous,the contents in it account for 40—56 percent.Potassium is stored mainly in branches and roots.Calcium is stored mainly in trunk (40—57 percent of the total).Paulownia forest absorbs 320kg/ha nutrient element a year,89kg of which is distributed into newborn organisms,132kg returns to litter fall and 102kg is leached away by rain and stemflow. The absorbed nutrient elements in a year include calcium (104kg/ha·a),potassium and nitrogen(70—100kg/ha·a),phosphorous and magnesium (26—27kg/ha·a).The nutrient cycling percentage of paulownia forest is high, 74% of which is returned to the forest floor and only a small is consumed. So long as certain manure is added,productive forces can be well maintained.