The Himalayan orogenic belt is a natural laboratory for studying plate tectonics. Located at the core of the Himalayan orogen, the Greater Himalayan Sequence (GHS) is the key to revealing the collisional orogenesis and orogenic evolution. This paper presents the petrography, zircon and monazite U-Th-Pb chronology and geochemistry of the GHS granitic gneisses from the Yadong area. The field survey and microstructure show that these rocks have the mineral assemblage of plagioclase + K-feldspar + quartz + biotite + garnet, and have experienced a metamorphism of the upper-amphibolite to granulite facies with partial melting. Chronology and geochemistry indicate that the protoliths of granitic gneisses include the Neoproterozoic (~800 Ma) granodiorite and the Silurian (~440 Ma) granite, both of which experienced metamorphism in Miocene (~16 Ma). The Neoproterozoic granodiorite has negative εHf(t) values of -16.4~-12.2, and crust model ages t_DM^C of 3.11~2.79 Ga, suggesting that the rock was derived from partial melting of the ancient lower crust. The Neoproterozoic granodiorite and Silurian granite have similar geochemical characteristics to arc granitic rocks, with negative anomalies of high field strength elements Nb, Ta, P and Ti. The present study reveals that the Greater Himalayan Sequence has experienced multistage tectono-thermal events, including not only the Cenozoic collisional orogeny but also the Neoproterozoic magmatism associated with the evolution of the supercontinent Rodinia as well as the surrounding Andean orogeny after the Paleozoic formation of Gondwana.