Abstract: An experiment was conducted to investigate the effects of grazing treatments (sheep or cattle grazing, mixed grazing of cattle and sheep, and no grazing) on root architecture of Stipa krylovii in the desert steppe of Inner Mongolia. After grazing for 14 months (two growing seasons), cattle grazing and mixed grazing of cattle and sheep significantly increased nitrogen content of soil at 10-20 cm depth. Cattle grazing improved nitrate content, while the mixed grazing of cattle and sheep mainly improved organic nitrogen content. The aboveground biomass in no grazing area was significantly greater than that in each grazing area, while belowground biomass was insignificantly different among the treatments. After grazing for 14 months, 5 of 6 root architecture parameters of S. krylovii showed no differences among all the treatments. The classification of root diameter showed that root length, volume and surface area in diameter of 4.0-4.5 mm and 2.5-3.5 mm in no grazing area were significantly greater than those of the grazing areas. Overall, 14 months might be too short to change the soil and root architecture of the dominant plant, which deserves further observation.