In the Yanshanian orogenic belt, volcanic eruptions were most strong and freque nt in the Mesozoic. According to the tectonomagmatic cycles, the eruptions can be divided into four stages: the Early Jurass i c Nandaling, the Late Jurassic Tiaojishan, the Early Cretaceous Donglingtai and Donglanggou stages. The distribution of volcanic rocks shows that the Early Jura ssic er uption belts are nearly EW, the late Jurassic belts are NE, and the Early Cretac eous belts are N NE. The volcanicsedimentary basins have different characters: the Early Jurass ic basins are inherited downwarped basins, the late Jurassic ones are inherited fault basins, and the Early Cretaceous ones are neogenic stacked fault basins. There are three volcanic eruption types: the Nandaling eruption belongs to the Hawaiian type, th e Tiaojishan eruption belongs to the Strombolian type; the Donglingtai eruption belongs to t he Plinian t ype. From the Early Jurassic to the Early Cretaceous, the compositions of magma changed from the basic, intermediate to the acidic magma.