This study uses tooth meso-and microwear together with bone collagen stable isotope ratios (carbon (δ¹³C), nitrogen (δ¹⁵N), and sulphur (δ³⁴S)) to investigate diet and human utilization of two middle Holocene (~5 ka cal B.P.) populations of wild horses, Equus ferus from northwest Europe. The results of the mesowear analysis places one population (Ginnerup, Denmark) amongst extreme grazers and the other (Hüde I, NW Germany) amongst less-abrasion dominated grazers. These are contrasted by microwear, which suggest that both populations were killed, when browsing. The low microwear scratch variation in the Ginnerup population suggests that the duration of the mortality event(s) was short and confined to the same season. The mesowear analysis further suggests that the horses at Hüde I included more browse in their diet than at Ginnerup. This is supported by depleted δ¹³C values in the Hüde I population. The δ³⁴S values also differ between the two sites. The higher values at Ginnerup (a coastal site) compared to Hüde I (an inland site) is interpreted as an effect of marineinfluenced sulphur-enriched rainfall. Furthermore, the rather consistent δ³⁴S values at the two sites respectively suggest that the horses killed were from locally available herds. In general, δ¹³C and δ¹⁵N isotope values of horses and other animals from Ginnerup and contemporary nearby sites show tendencies towards more depleted values in the horses and other wild herbivores than in livestock. We suggest that this is a result of niche partitioning and hunting pressure. The results presented here further our understanding of some of the youngest known never-domesticated populations of wild horses Equus ferus in northwest Europe.