The formed age of basalt from Daxizhuang, Jiaozhou is between Mesozoic and Cenozoic and this offers a good opportunity to trace the deep processes and the lithospheric evolution. The Pb isotopic compositions of basalt from Daxizhuang are comparatively uniform with n(206Pb) n(204Pb) (t) from 18.18 to 18.24, n(207Pb) n(204Pb)(t) from 15.42 to 15.44 and  n(208Pb) n(204Pb)(t) from 37.87 to 37.96 and show the most close affinity to the DMM endmember among the whole Mesozoic—Cenozoic basic rocks in eastern China. This kind of isotopic character suggests it derived from comparatively pure asthenospheric mantle source which was similar to that of the Pacific MORB. Based on contrastive studies on the isotopic data of the Mesozoic—Cenozoic basic rocks from eastern China, it is suggested that the Mesozoic isotopic enriched lithospheric mantle had transformed into Cenozoic "juvenile" oceanlike ones in eastern North China Craton. The local underneath asthenospheric materials was comparative pure just after the lithospheric thinning and then, during Cenozoic, asthenosphere, isotopic enriched lithospheric mantle and the materials derived from subducted slab of the Pacific plate contributed their isotopic imprint to the basalts. The isotopic evolution of Mesozoic to Cenozoic basic rocks infers that delamination was dominant mode of the lithospheric thinning. The delaminated enriched lithospheric mantle plus the ancient lower crust reacted with the asthenosphere and they constituted the magmatic source of the Cenozoic basalts. The deep processes which took place in eastern south China were different from that of eastern North China Craton. From NNW to SSE, contribution of materials derived from subducted slab of the Pacific plate progressively increased in the asthenospheric mantle source from which the Cenozoic basalts derived with little trail of enriched lithospheric mantle. Transformation of the lithospheric mantle also took place in eastern south China, a similar process to that in eastern North China Craton with the dominant mode being metasomatism of melt instead of delamination.