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Slab rollback is one of the primary processes in shaping tectonic framework. However, in the Tibet–Himalaya orogen, the timing of the Neo-Tethyan slab rollback remains controversial. In this contribution, we investigated an early Paleocene (ca. 62 Ma) A1-type granitic intrusion (South Gongshan) from the Gaoligong–Tengliang–Yingjiang (GTY) area, SE Tibet. It is mainly characterized by high 10,000*Ga/Al ratios (4.0–9.1) and extremely high HFSEs contents (Zr + Nb + Ce + Y = 669–3146 ppm), with relatively low Y/Nb ratios (0.8–1.1). The samples collected from the intrusion exhibit high zircon εHf(t) (+1.1 to +5.7) and whole-rock εNd(t) values (− 0.8 to − 3.1). Geochemical data indicated that it was probably produced by extreme FC of asthenospheric mantle-derived basaltic magmas. Together with results from convergence rate between India and Asia, the emplacement of the South Gongshan intrusion was likely to be associated with a transition from flat to steep subduction triggered by the Neo-Tethyan slab rollback. We proposed that the Neo-Tethyan slab rollback beneath the GTY area might have occurred at ca. 62 Ma. [ABSTRACT FROM AUTHOR]