The Early Permian volcano sedimentary sequences of Ongniud Banner consist mainly of andesite, rhyolite, perlite, volcanic breccia, tuff, tuffaceous sandstone, siliceous rock. Rock assemblage and sedimentary formations indicate that are of fore arc basin sedimentary feature between subduction zone and island arc in Early Permian. The volcanic rocks from Elitu Formation have SiO2=50.23%~73.56%, Mg#=6.21~49.54, Na2O+K2O=5.27%~10.73%, Na2O/K2O=0.36~4.17, belonging to high K cal alkaline (HK CA) ~ shoshonite (SHO) series. The volcanic rocks are characterized with（La/Yb）N=5.52~9.89, mid intensive negative Eu abnormality, LILE enrichment such as Rb, K, La, Th and HFSE depletion such as P, Ti, Ta, Nb, and indicating that magma was formed in the tectonic setting of the island arc and active continental margin related to the plate subduction. R1 R2 diagram also indicates that volcanic rocks are generated at syn collision or post orogenic period, perhaps representing the mid later subduction stage of the Palaeo Asian Ocean Plate and North China Plate. Taken together, it suggests that the region located still in the Palaeo Asian Ocean, rather than the intracontinental taphrogenic trough in Early Permian.