By the data and methods of cores, thin section, whole rock analysis, well logging, seismic and so on, this paper analyzes the volcanic characteristics and eruption models of the First Member of the Yingcheng Formation in Xingcheng area. The main type of volcanic rocks is acid igneous rock. According to the principle of “ingredients + genesis + structure”, six volcanic rocks, such as the rhyolite, volcanic breccia, are classified. In vertical direction, the percent of SiO2 increases from the bottom to the top, forming an integrated eruption cycle from the basic igneous rock to the acid igneous rock; In plan, the distribution of the volcanic rocks shows the characteristics of low area filling, the early volcanic rocks are mainly distribute in the middle and southern areas of Xingcheng, and the later distributed in the whole Xingcheng. On the basis of the characteristics of the volcanic rocks and their distribution, the model of the volcanic eruption is concluded. There are two erupting models, one is the central vent eruption, and the other is the eruption of fissure type.