Being a crucial subsistence strategy for the steppe communities, transhumant pastoralism has played a pivotal role in facilitating early communication of East and West civilizations. However, despite its significance, there remains a paucity of research regarding how and when transhumant pastoralism emerged at the eastern end of the Eurasian Steppe. Situated at the crossroads of East-West exchanges, the Tongtian Cave site has yielded a diverse range of archaeological materials, including sheep bones, sheep coprolites, and the earliest remains of wheat and barley in China. In order to explore the herding strategies employed at the Tongtian Cave, the microfossil contents from site's stratigraphy and the sheep coprolites are investigated in this study. Analytic results reveal the presence of elm tree pollen and probably phytoliths within the coprolites, suggesting that the site once served as a spring pasture. Wheat remains recovered from the same stratum as the coprolites date the transhumant practice at the site as far back as ca. 4300 B.P., establishing the Tongtian Cave as not only the earliest pastoralist site in China but likely also in the eastern Eurasian Steppe. Overall, our studies of the Tongtian Cave materials provide crucial evidence that deepens our understandings of the timing and mechanism of the eastward expansion of transhumant pastoralism across prehistoric Eurasia. The methodological potential of pollen and fungal spore analyses in revealing the seasonality of ancient site use is also explored in this article.