The deformation style of the deep crust during the post- orogenic extension can reflect the tectonic activities of deep lithosphere, and should be the key issue in studying the kinematics of the deep lithosphere. Based on the field observation and structural texture in the North Dabie Mountains, numerical modeling was conducted for the post- ogogenic extensional deformation structure of the Dabieshan orogen to systematically analyze the vertical spatial distribution of rock deformation mechanism of the extensional deformation and further reveal the deformation styles of middle- lower crust during the post- orogenic extensional process. Field observations show that stretching lineation has distinctive preferred orientation in the margin areas of the North Dabie dome, gradually deceases towards the middle of the dome, and then is enhanced again in the core of the dome. Kinematically, the dome of North Dabie Mountain shows a consistent NW- trending shearing in hanging wall. Based on the results above, numerical modeling in this study indicates that flow styles of the North Dabie middle- lower crust is generally the combination of simple penetrative shear deformation and pure shear deformation. Simple shearing in the profiles shows distinct decreasing toward the core from top and bottom and, flow mode in the center of the middle- lower crust is dominantly pure shearing. It can be concluded by the authors that the flow model of the North Dabie middle- lower crust may result from the recession of the deeply subducted pacific plate and the ductile collapsing of the thickened orogenic crust.