Mesozoic volcanic activities experienced three stages, namely the Late Triassic-Late Jurassic initial stage, the Late Jurassic flourishing stage and the Cretaceous weakening-withering stage. The three stages, controlled by the same tectonic mechanism, show remarkable differences and also transitional characteristics in such aspects as volcanic activities, rock assemblages, petrochemistry and geochemistry. Studies show that the formation of Mesozoic volcanic rocks was intimately related to the subduction of the Pacific plate towards the Eurasian plate, and these volcanic rocks can be called Zhejiang_Fujian type volcanic rocks.