Abstract: With the Stipa breviflora desert steppe in Siziwang Banner of Inner Mongolia as the research object, the pattern distribution types, pattern scale and clump intensity of 3 kinds of dominant plants as S. breviflora, Cleistogenes mutica, A rtemisiafrigida with different stocking rates were studied by using t test of diffusion coefficient, mean crowding intensity, clumping index, patchiness index, Green index, Cassie index and so on. The results showed that the distribution types of S. breviflora, C. mutica, A. frigida were clump distribution. In CK area and middle pasturing area the clump intensity of 3 kinds of plant in order was C. mutica 〉 A. frigida 〉 S. breviflora and in light and heavy pasturing area, their clump intensity in order was A. frigida 〉 C. mutica 〉 S. breviflora. With the degradation of desert steppe, C. mutica and A. frigida would become as the main populations in community.