Cretaceous volcanic rocks outcrop expensively in the adjacent area of Zhejiang-Fujian provinces and can be subdivided into the Lower & Upper Volcanic Series. The earlier Lower Volcanic Series are widely-spread felsic volcanic rocks formed at early stage of Early Cretaceous. They belong to weakly peraluminous high-K calc-alkaline series, are enriched in LILE (such as Cs、Rb、Ba、Th、K、Pb) and LREE without evident Eu anomalies, depleted in HFSE (such as Nb、Ta、Ti、P), show low εHf(t) values (-20.43~-6.39) and old crustal model ages (TDM2 mostly between 1.8 and 2.2Ga). The later Upper Volcanic Series are felsic volcanic rocks which formed at late stage of Early Cretaceous and expose only in faulted basins. They belong to metaluminous high-K calc-alkaline series, contain similar LILE and LREE to the Lower ones, but have evident Eu anomalies, lower SiO2 & total alkaline contents and higher εHf(t) (-10.00~-4.51). Both the Lower and Upper Volcanic Series show decreasing ΣREE and differentiation degrees of LREE with time, they are mostly high-Sr rhyolitic rocks formed in active continental margin setting, and derived from partial melting of Proterozoic basements caused by underplating of mantle magmas. However, the Upper Volcanic Series underwent more crust- and mantle-derived magmatic mixings. Different from above rocks, the lava at the top of Xishantou Formation is Shoshonite series high-Sr trachyandesite. It is a kind of very rare rock in coastal Southeast China, enriched in Sr, Ti, Co, Ni but lower εHf(t) values, and is inferred to result probably from fractional crystallization of mantle-derived basic magma. Based on comprehensive comparisons of Late Mesozoic volcanic rocks, it is summarized that the crust-mantle interactions in Southeast Coast of China incerased temporally from Middle-Late Jurassic to late stage of Early Cretaceous, and weakened spatially from south to north.