Research Question: combined the method of the micro histological analysis of feces and the fieldwork observation from March to May in both 2012 and 2013, the spring diet of the Asiatic Wild Ass (Equus hemionus hemionous) was investigated along the border of China-Mongolia in the center part of Inner Mongolia Autonomous Region, PRC. Methodology: direct observation for determiningfloristics of plantsin the diet of Asiatic wild ass; analysis spring diet of Asiatic wild ass with the method of micro histological analysis of fresh fecal simples collected from various settlement of plants in the active field of Asiatic Wild Ass; calculation for the appearing frequency F (%) of each plant in the combined fecal simples of Asiatic Wild Ass. The result will be transfer into D (the average density of distinguish fragment in each visual field) by the formula F = 100（1 - e -D）, and then transfer into DR (related density = individual density of distinguish fragment/ the sum of the densities of fragments×100 %). Additionally, the DR could be considered as the elements of composition of the herbaceous diet. Use the SPSS-13.0 to process the data. Result: The result of micro histological analysis of feces shows that there are 45 species of plants belonging to 25 families in the spring diet of Asiatic Wild Ass in the center part of Inner Mongolia Autonomous Region. Specifically, the graminaceous plants (Gramineae) took 54.88%, chenopodiaceous plants (Chenopodiaceae) owned 17.37%, tamarisk (Tamaricaceae) shared 6.64%, and leguminous plants (Leguminosae) 6.52% (Figure 2. The food composition of Asiatic wild Ass in spring). While the primary plants consumed were as follows: Krylov needlegrass (Stipa krylovii) (24.38%), Lovely achnatherum (Achnatherum splendens) (15.11%), Salsola passerine (Salsola passerine) (9.92%), Green bristlegrass herb (Setaria viridis) (6.97%), Humifuse euphorbia herb (Reaumuria soongorica) (6.64%), Bassia dasyphylla (Bassia dasyphylla) (5.67%), and Scabrous cleistogenes (Kengia squarrosa) (5.10%), which took the major part (73.79%) of the diet together (Table 1. The food composition and selectivity of the Asiatic wild Ass in winter). Conclusion: The spring diet of Asiatic Wild ass in the center part of Inner Mongolia Autonomous Region had high diversity. Less selection is the outstanding feature of the spring diet, which could be considered as the adoption of spring cold and drought of the area.