There is a NE-SW extend saddle-shaped lower ridge between Awati and Manjiaer sags,central Tarim Basin. It is proposed as the separate boundary between these two sags. The faults of this ridge are studied on the basis of 3D seismic data interpretation. The faults development in the ridge are classified into 4 stages: 1)Nanhua-Ordovician normal faults are related to the breakup of Rodinia supercontinent,and can be further divided into 2 sub-stages,Nanhua-Sinian and Cambrian-Ordovician. Nanhua-Sinian normal faults directly related to the breakup of Rodinia,forming graben-horst structures. Cambrian-Ordovician normal fault were formed under the gentle extensional background of Tarim wandering in paleo-Tethys. These faults usually form negative flower structure. 2)Terminal Ordovician-Middle Silurian faults composed of terminal Ordovician-beginning Silurian detachment-thrust faults and compressive strike slip faults,forming fault-propagation fold and flower structure. The faults of this stage is related to the Kunlun Caledonian collisional orogeny. 3)Late Silurian-Carboniferous normal faults form typical negative flower-structure and usually group into transtensional fault zones. The formation of this stage normal fault is associated with the stress relaxation after Kunlun Caledonian collisional orogeny. 4)Permian normal faults were formed under the continental-rifting background of Tarim,and often deformed by the rift-related magmation. Permian normal faults usually group into graben-horst structure and negative flower structure,and form transtensional fault zones. Some Permian faults may inherit the Late Silurian-Carboniferous faults.