The Dongkeng Basin is located in the eastern section of Nanling tectonic belt. The rhyolite as the acidic end-menber of bimodal volcanic rock association, is the most ancient rhyolite that distinguish from the southern China during the Yanshanian period. The rhyolites in the study area is characterized by high SiO2, K2O, and low MgO, CaO, TiO2, and plot in the field of sub alkaline and weakly peraluminous series in the SiO2 vs K2O and A/CNK vs A/NK diagrams. The primitive mantle（PM）-normalized trace element patterns of all of these rocks are enriched in large ion lithophile elements（LILE, such as Rb, Ba, Th, U）and depleted in high field strength elements（HFSE, such as Nb, Ta, Hf, Zr）. The rhyolite are characterized by light REE（LREE）enrichments, with weakly differentiated heavy REE（HREE）and significant negative Eu anomalies, which shows typical M-type tetrad effects. Moreover, the Sr-Nd-Pb-O-Hf isotopic compositions show low ；（87Sr/86Sr）i,（206Pb/204Pb）i,（207Pb/204Pb）i and（208Pb/204Pb）i, high εNd（t）、εHf（t）and δ18OV-SMOW‰ value, and low TDM2（Nd）and TDM2（Hf）. The comprehensive analysis of rhyolite's geochemical characteristics indicates that Dongkeng Basin rhyolite originates from the Neoproterozoic of depleted mantle and enriched mantle type-II and mixed with a small amount of ancient light lower crust during the Early Jurassic and early products of partial melting of extensional tectonic environment, providing the petrology of evidence for the early stage of Early Jurassic in Nanling belt which crust is normal thickness.