In recent year，m any achievements in scientific research on M esozoic and Cenozoic geodynamics setting inSoutheast China have been made，which include mantle source，lithosphere thinning，lithosphere extensionevents and tectonics setting in southeast China． Geochemical and isotopic studies indicated that m antle sourceare composed of depleted asthenospheric mantle and enriched lithospheric mantle beneath the crust，thesubcontinental lithospheric mantle(SCLM )are predominantly EM 11 lithospheric mantle in the Mesozoic whileasthenospheric mantle in the Cenozoic in southeast China．It is suggested that the lithoshpheric thinning tookplace in the late M esozoic accompanied by basaltic magma uderplating，which has complicated lithosphericaccretion and thinning process beneath the crust in southeast China． Several lines of evidences demonstratedthat lithospheric extension occurred in this region during the Late M esozoic to Cenozoic． M oreover， localextension occurred in inland area of southeast China in the Jurassic while regional extension in the Cretaceous insoutheast China．The tectonic setting that accounts for M esozoic magmastism in southeast China has been anissue of little consensus since the last tWO decades and focused on whether the extensive magmatism province arerelated to Pacific plate subduction in the regions． From available data，it is thought that Cretaceous mantlesources have affected by Pacific plate subduction and basaltic magma underplating resulted in the lithosphericthinning and subsequent lithospheric delamination and asthenospheric upwelling． However， lithosphericextension- thinning and its deep process beneath the crust in the M esozoic to Cenozoic in southeast Chinaremains to be further studied．