As the northern boundary of the north Dabie dome, the Xiaotian—Mozitan ductile shear zone separates the North Dabie unit from the Beihuaiyang (north Huaiyang) unit. It strikes NWW—SEE and dips toward NNE. The shear zone is interpreted as having resulted from postorogenic extension in the Dabie orogen. Field investigation as well as analyses of quartz Caxis fabric and kinematic vorticity for the shear zone mylonite demonstrates that the shear zone mostly experienced sinistral motion under simple shear deformation. The disharmonious kinematic character in the middle part relative to the rest parts indicates that the shear zone had been rotated since its formation. The strain modeling limited with real fabrics shows that the shear zone originated from a horizontal, midcrustlevel ductile shear zone with shear sense of toptoNWW(280° ) and then was uplifted and rotated to its present attitudes by doming of the North Dabie dome. The western segment of the North Dabie dome experienced more intensely doming than its eastern segment, therefore leading to unequal uplifting and rotation of the shear zone. The shear zone and North Dabie dome both resulted from gravity collapse during Early Cretaceous. The current North Dabie unit was similar to the Cordillerantype metamorphic core complex.