Abstract: We in this article, have analysed 8 kinds of nutrient element within the body of Leymus chinense on cutting grassland. It has found out that Leymus chinense absorbs large quantity of nutrient from the element of N. Mg. Ca. K. and small quantity from the element of Cu. It has more quantity at roots than in leaves. Each nutrient element aborbed and accumulated is in highest quantity at the first period of its growth. And the quantity of accumulation reduces from time to time. The element of Na has its lowe quantity at the first and middle period of growth, but a sudden increasing tendency occurs at its last period of growth. Cu keeps its lower quantity from begining to the end with little change.The quantity of nutrient elements absorbed and accumulated from soil by Leymus chinense on cutting grassland is 40.27kg. per hectare each vear. The quantity of nutrient elements that has been brought out of the cutting grassland is 25.71kg. The survived nutrient elements in withered things and cut-stem-atuble of grass are 10.58kg. per hectare each year. Circulatory quantity that has returned to soil is 4.02kg. per hectare each year. Terefore, export quantity of nutrient element of Leymus chinense on grassland is much larger than import quantity. This is the essential reason why the fertility of soil reduces gradually, the grassland degenerated and produetive power falls down.