Neoproterozoic magmatic rocks are widespread in northwestern margin of the Yangtze block，and further works for petrogenesis of these rcoks have significant implications to understand the tectonic evolution of Rodinia supercontinent in this region.Methods: In this paper，we present zircon U Pb age， whole rock major and trace elements，and Sr—Nd isotopic compositions of the monzogranite from the northwestern margin of the Yangtze Block, Micang Mountain.Results: Monzogranite zircon U Pb result show that the crystallization age of 742.1 ± 5.9Ma，which belongs to Neproterozoic granites. The Pinghe monzogranites are characterized by relatively high SiO2 （76.84% ~ 80.08%）contents，enriched in alkali（Na2O + K2O=7.64% ~ 8.99%） and potassium （K2O/Na2O=0.91~1.36），and low P2O5 contents. These rocks belong to metaluminous granite with A/CNK=0.77 ~ 0.89. They also show high REE compositions，enriched in LREE, Rb，U，Th，K，Pb and depleted in Ba，Nb，Sr，P，Zr，Ti，and a strong negative Eu anomaly (δEu=0.05 ~ 0.13). Isotopic results of these rock reveal evoluted Sr and Nd n(87Sr)/n(86Sr) = 0.747067 ~ 0.795283，n(143Nd)/n(144Nd) = 0.512472 ~ 0.512661，εNd(t)=+3.6 ~ +5.2），with two stage model age of 0.96~1.07Ga.Conclusions: In combination with geochemistry, isotopic signatures and contemporaneous geological events of Micang Mountain, we argued that the Pinghe monzogranites are high K calc alkaline and high fractionated I type granites, which derived from partial melting of lower crustal juvenile basaltic rocks，and subsequently undergone crustal contamination during the upwelling process. It was generated in an extensional tectonic setting, regarded as the precursor of the Neoproterozoic break up of Rodinia supercontinent.