Significance We undertook an ancient genomic DNA investigation of large animal remains dated ∼5,200 y B.P. from the Tibetan Plateau. We provide compelling evidence that the present-day low-latitude tropical inhabitants Bos gaurus and Dicerorhinus sumatrensis once roamed as far north as the margin of the northeastern Tibetan Plateau (NETP) during the late Neolithic, pushing the historical gaur distribution from ∼29°N to ∼34°N. Further multidisciplinary exploration indicates that a high summer temperature in the late Neolithic might have facilitated the northward expansion of these tropical animals to the NETP, which enriched the biodiversity of wildlife and contributed to the exploration of the Tibetan Plateau as one of the last habitats for hunting game in East Asia.