In recent years, the species diversity and aboveground biomass changes of steppe plant communities caused by grazing intensity have been hot issues in steppe ecosystem research. This paper takes the Stipa krylovii steppe of Xilin Gol in the Inner Mongolia as the research object, explores the relationship between characteristics of plant community structure, species diversity and aboveground biomass, and clarifies response to different grazing intensities. The results showed that the plant community structure gradually succeeded in the direction of degradation with the increase of grazing intensity. The height of the plant community gradually decreased (P<0.05) while the density of that gradually increased (P<0.05), and the overall coverage showed a downward trend (P<0.05). The aboveground biomass of plant communities and the dominant species of the original community showed a general downward trend (P<0.05), while that of the degraded indicator species gradually increased (P<0.05). The Margalef index, Pielou index, and Simpson index of community species under mild and moderate grazing conditions were significantly higher than those of heavy grazing (P<0.05). Aboveground biomass was positively correlated with Shannon-Wiener index, Margalef index and Pielou index, but showed a negative correlation with the Simpson index. In summary, the structure and function of the Stipa krylovii steppe plant community produce different responses in different grazing intensities, and moderate grazing is beneficial to increase the community's species diversity and biomass.