Abstract: In order to explore the interspecific relationship of the community in Stipa breviflora desert steppe in Siziwang Banner, Inner Mongolia, on the base of sample plots investigation on its community, the interspecific correlations of 105 species pairs from 15 kinds of plants were analyzed by using research methods of X^2 test, Pearson coefficient and Spearman rank correlation coefficient. The result showed that, the most interspecific community in Stipa breviflora desert steppe in Siziwang Banner had the negative correlation. The number of species pairs with significant and extremely significant correlation was little. The most of species pairs between dominant species showed significantly negative correlation and the number of species pairs between the dominant species and other species with negative correlation was more. It indicated that species niche of the community was differentiated and the species was independent, but the competition to resource availability was fierce and the community was in development and succession.