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The ecological stoichiometry is the study of investigating balance of energy and elements affected by organisms and their interactions in an ecosystem. In animal grazed grasslands energy and elements go through complex interactions. We examined the effects of different animal stocking rates on the elemental stoichiometry of three dominant grass species (Stipa bungeana (Sb), Lespedeza davurica (Ld), Artemisia capillaries (Ac)) grown on the loess plateau of China. The experiment was conducted at Tianshui Grassland Research Station of the Lanzhou University, located in Huanxian County, Gansu Province, Western China. Twelve experimental plots (100 m�50 m) were established in 2001 with similar botanical composition. Tan sheep lambs grazed rotationally in three replicated 0.5 ha plots of four stocking rates (0, 2.7, 5.3 and 8.7 sheep/ha). Plant samples were collected in July to August in each year since 2001 to 2015 and the elemental composition (C, N, P, Zn, Mg, Fe, Mn, Ca, Cu ) and the ratios of C/N, C/P and N/P were measured. We also investigated the effects of rainfall and temperature. The 15-year measurements indicated stocking rates had no significant effect on the elemental composition of the plant species but the effects of plant species were significant. The C concentration was stable over time in all three species. The N concentration of the Ld was higher than other two species. The P concentration decreased 2001 to 2010 in all three species. Trace elements composition of the three species varied in different years. The C/N ratio was greater in Sb while N/P ratio was greater in Ld compared to other species. We found significant relationships of elemental composition and rainfall. Our results indicate that plant identity and the environmental factors contribute more to the ecological stoichiometry of animal grazed grasslands of loess plateau than the grazing management. Key words: Grazing, Loess plateau, ecological stoichiometry