Abstract: The Emeishan mantle plume activity is an important geological event in Phanerozoic. To deepen our understanding on the evolution of the Emeishan mantle plume activity in the Wumengshan area of northeastern Yunnan, the isotopic chronology, zircon trace element, zircon Lu−Hf isotopes and dental spines of the middle and upper tuffs of the Maokou Formation in this area were investigated, which is a new direct petrology evidence for the evolution of Emeishan mantle plume activity in the Wumengshan area of northeast Yunnan Province, and the result shows that the zircon U−Pb age of the uppermost tuffs of the Maokou Formation is 268.7 ±1.7 Ma(MSWD=0.89, n=8), consisting with the Jinogondolella aserrata, which is a typical molecule of the Permian Guadalupian Wordian. The zircon trace element characteristics of the uppermost tuffs of the Maokou Formation show affinities of basalt magma origin and continental arc−type tectonic setting, together with a high Th/Nb value, indicating a volcanic activity pre the large−scale eruption of the Emeishan Large Igneous Province. The ε_Hf(t) value of the zircons of the Maokou Formation is −6.7~11.6, indicating that the volcanic activity pre the Emeishan mantle plume was strongly influenced by the mantle plume materials and more crustal materials. The discovery of tuff in Maokou Formation shows that the Emeishan mantle plume has undergone a small−scale magmatic eruption in the Wumengshan area during the in the Permian Guadalupian Wordian. During this period, the mantle plume mainly played the role of conducting heat to the lithosphere and melting some mantle materials, which added new evidence for the establishment of Emeishan mantle plume model.