Abstract: In this paper, mixed-sowing artificial grassland in the temperate agro-pastoral zone is taken as the research object, The changes of aboveground and underground biomass of Leymus chinensis and Medicago sativa L. under ditterent grazing patterns were analyzed. The effects of carbon allocation on dominant species and carbon density of artificial grassland were researched. The results indicated that rotational grazing can ettectively relieve the grassland pressure, and a reasonable grazing system can improve the grassland productivity. The palatability of sheep changed with the ditterent grazing systems. Grazing patterns have ditterent effects on grassland vegetation carbon density and soil carbon density. As a result of continue grazing, both the carbon density and soil carbon density of grassland vegetation were significantly reduced, and the rotational grazing was at the same level as that of the management of grazing prohibition. In the tested artificial grassland, the ditterent grazing systems have significant effects on pasture productivity and carbon density. Soil carbon density accounts tor a large proportion of the carbon density in artificial grassland and decreases with the increasing of soil depth.