he Tongbai Shan(mountains)is located in the east part of the central orogenic belt of China，crossing the Hubei and Henan Provinces. The construction process of it has attracted the major attention of geologists worldwide. Through field geological investigation，we found that the northern slope of the Tongbai Shan is steep，while the southern slop is relatively flat，suggesting that the Tongbai Shan may have experienced southward tilting. The Yindian fault constitutes the southern boundary of the Tongbai Shan，present with dextral strikeslip movement. It is composed of mylonite，which can be trace to the highest peak of the Tongbai Shan，namely Taibaiding(1140 m). Beneath the mylonite is the Tongbai complex，which constitutes the main part of the Tongbai Shan. Although the attitude in the complex is orderless，stretching lineation remains stable，elongated in northwestsoutheast directionin. We can infer that prior to the tilting movement occurred，the Yindian fault was formed as a lowangle normal fault with stretching lineation plunging into northwest，we name it as the Taibaiding detachment fault. Kinematics and microstructure studies show that originally the Tongbai complex was located in the lower crust beneath the east Qinling Mountains and was brought to the surface as a result of the lateral extrusion along the Taibaiding detachment fault，due to the Mesozoic collision between the north and south China. 40Ar/39Ar geochronology results show that the tectonic uplift of the Tongbai Shan initiated in Late Cretaceous(102～85 Ma). The subsidence of the Nanyang Basin，initiated in Cretaceous time，is directly controlled by the lateral extrusion of Tongbai complex，formed as a half graben，overlying on the metamorphic complex of the Tongbai Shan along the Taibaiding detachment fault and overlap on the preMesozoic rocks with different age of the east Qinling belt.