The paleogeographic reconstruction of Rodinia supercontinent and the scheme of blocks have always been the focus and frontier of earth scientists at home and abroad. At present, the origin and paleogeographic location in the Rodinia supercontinent of the blocks in the Qinghai-Tibet Plateau are not clear. The comparative study of magmatic events is one of the effective methods to solve this problem. In this paper, LA-ICP-MS zircon U-Pb dating, petrogeochemistry, and zircon Hf and whole-rock Sr-Nd isotopic analyses of the granitic gneisses from the Amdo microcontinent in the central Tibetan Plateau are reported. The protoliths of these granitic gneisses were formed at 802~801 Ma, have heterogeneous zircon Hf and homogeneous whole Nd isotopic compositions (εHf( t )=9.4~+1.9; εNd( t )=4.8~3.4) and ancient crustal model ages (2289~1575 Ma), and were probably generated by melting of mantle-modified Proterozoic crust and subsequent extensive crystallization differentiation. All samples have low P2O5 contents, that is negatively correlated with SiO2 contents, and the samples contain a small amount of hornblende minerals, which is similar to those of I-type granite. Some rocks have high contents of high field strength elements (Zr+Ce+Nb+Y＞350×10^-6) and zircon saturation temperature (＞800℃) of A-type granite affinitiy. Finally, we propose that the granitic gneisses were probably formed in a back-arc basin environment, and could be compared with coeval magmatic rocks in Madagascar, Seychelles, and western India. This work provides new information for reconstruction of the Rodinia supercontinent.