Abstract: The elemental characterstics of the root system of plants of the sand land of pasture of Inner Mongolia are reported in this paper.These results show that the average contents of N, P, K, Si, Na, Fe and ash in 51 species of plant root system are 1.08%, 0.104%, 0.686%, 0.811%, 0.049%, 0.030% and 6.41% respectively. The average contents of N, P, K, Na and ash in the root system are lower than those in the plant system above ground, for same element, but the contents of Si and Fe in the two systems are the reverse: the contents of these tow elements in the aboveground system being lower than those in the root system. vely interrelated.