The coupling relationship between the Bohai Bay basin and Taihang Mountain has been studied based on geological, geophysical and structural landform data. The basin and the mountain were formed by Cenozoic rifting on the basis of the North China peneplain, which was formed in the Late Cretaceous. The piedmont fault of Taihang Mountain is a large detachment structure in the upper crust, and the basin's subsidence and the mountain's upheaval occurred by its extension and detachment. The basin's staggered subsidence and the mountain's discontinuous upheaval took place at the same time. The differences of the crust and upper mantle structures in the area were probably formed during the basin/mountain formation period. They are tectonic sections formed by detachment between the layers, brittle/ductile transition and extension/contraction. The basin and the mountain have the same formation mechanism and dynamical condition. The upheaval and lateral diversion of the asthenosphere under the basin produced ductile deformation of the mantle lithosphere and the lower crust from bottom to top, which not only caused the top layers to be extended and rifted to form basin, but also pushed the materials in the same layer in the mountain to the west, so that they were shortened, thickened and upheaved, giving way to the basin's extension. The mountain was formed accompanying the basin's development.