The origins of orogenic belts and basins are two hot topics of current geoscience research. The first part of this paper briefly introduces various main concepts of orogeny and basin formation. Among these concepts, those of the formation of mountains by compression and the formation of basins by extension are dominant position. It has been generally considered that orogenic belts and basins are formed by different geodynamic mechanisms. In light of China's actual geological conditions it puts foreward that mountain ranges and basins are formed by a unified geodynamic mechanism, i. e. their formation is due to the after-effect of compression-extension-isostat-ic orogeny and basining.