Abstract: The spatio-temporal distributions and tectonic environments of the Meso-Cenozoic igneous rocks in SE China and Japan are discussed mainly, as well as their similarities and differences are summarized in the paper. There are different magmatic evolution histories during Indosinian and Yanshanian periods (190-170Ma) in SE China and Japan. The S-type granites of peraluminous and weak peraluminous were most widespread during 165-150Ma in SE China, but there was an inactive period of the magmatism during 170-130Ma in Japan. The large scale of the volcano-intrusions were taken place during the Late Yanshanian period both SE China and Japan, which all were produced by the initial subduction-collision and later extension- break up of the Kula-Pacific plate toward Eurasian continent. Large-scale volcano–intrusions in Japan were later (130Ma) than SE China, and continued to the Eocene (45Ma). Both SE China and Japan were situated in the tectonic environments of continental extension before the Japan Sea was opened（>15Ma）, and the SE China and Japan were located in completely different settings of the tectonic evolution after the Japan Sea was opened（<15Ma）.