Reintroduction programs of large herbivores require an understanding of foraging ecology, as diet influences both population persistence and vegetation impacts. Dietary information in reintroduced species provides insight into ecological integration and potential vegetation effects, essential for assessing long-term sustainability. We used DNA metabarcoding of fecal samples collected across seasons and space to characterize the diet of the reintroduced Asiatic wild ass (Equus hemionus) in the hyper-arid Negev Highlands, Israel, where vegetation is sparse. We detected 108 plant genera from 45 families, revealing a diverse diet composed primarily of native woody and herbaceous plants. Summer diets exhibited higher beta diversity and stronger spatial structuring, suggesting increased reliance on locally available vegetation when plant availability declined. Females consistently showed lower dietary variability than males, likely reflecting reproductive and social differences between the sexes. Despite pronounced seasonal and spatial variation, we found no evidence of selective foraging on specific taxonomic groups, including rare or vulnerable plant taxa. Consumption of agricultural or garden-derived plants was minimal. Overall, these results highlight the dietary flexibility of the Asiatic wild ass, where opportunistic foraging within sparse and unpredictable desert resources has likely facilitated its persistence. The dominance of native plants in the diet, limited use of human-associated vegetation, and absence of detectable pressure on sensitive taxa suggest that the reintroduced population is ecologically integrated within its historical habitat and that its current ecological impact appears sustainable. More broadly, this study demonstrates how metabarcoding-based dietary data can be used to assess ecological integration and vegetation impacts in large herbivore reintroductions, emphasizing the need for continued dietary monitoring as climatic and anthropogenic pressures intensify.