A suite of granitic gneiss was identified new within the Precambrian Shigu metamorphic complex to thenorthwest of Yunnan, southeastern margin of the Tibet plateau. LA- ICP- MS Zircon U- Pb dating indicates that, the granitic gneiss was formed during early Neoproterozoic, and the weighted mean ages of 206Pb/238U were 790±11 Ma (MSWD=2. 1, n=10) and 814± 15 Ma (MSWD=5. 7, n=9). Geochemical characteristics show that, the rocks were characterized by high silicon (SiO2=66. 05%~77. 16%), high K2O/Na2O (0. 90~9. 26, mean of 2. 57), MgO=0. 35%~3. 60%, TFeO=1. 02%~4. 86%,P2O5=0. 03%~0. 17%, and belong to strongly peraluminous granites, with A/CNK=1. 08~2. 51, aluminium- rich minerals (such as garnet and muscovite), and corundum molecules (av. 4. 72%). The chondrite normalized REE patterns of samples show enrichment of LREE ((La/Yb)N=1. 79～12. 34) and strong negative Eu anomalies (δEu=0. 21～0. 67). The primitive mantle normalized trace element diagrams show enrichment of Rb and U, and depletion of Ba, Ta, Nb, Sr, P and Ti. It is suggested that, the granitic gneiss protoliths resulted from partial melting of arenaceous rock with less mature and poor clay underhigh temperature conditions. They were formed in a post- collision tectonic setting, in response to the Rodinia supercontinent amalgamation in the Shigu area,northwest of Yunnan.