Combined with the orogenic belt, study on the dynamical mechanisms of extensional basins systematically is a new approach of continental dynamics research. This paper choose extensional basin in post collision stage for the object, and distinguish it from other types of extensional basin, and attempt to explore its continental structural properties. Paralleling to the spread of orogenic belt, the post collision extensional basin is preliminarily defined as a kind of hinterland extensional basin which controlled by the adjacent orogenic belt, and formed in the post collision tectonic setting of orogenic evolution. The progress of basin conversion and super implosion is closely related to the evolution of the coupled orogenic belt, that is, it sequel from foreland basin coupled with the syncollision orogenic belt into extensional basins coupled with the post collision orogenic belt. The essential mechanism of this kind of basin is removing mountain root after the crustal shortening and thickening effect. The thickened crust thinning is caused by delamination mainly. The delaminations of lower crust bring out mafic magmatism, and formed the rift and fault—depression on surface, which filled with fluvial facies sediments.