On the basis of the results of wide-angle and subvertical seismic reflection sounding and related geological data, the authors studied the crustal structure and ultrahigh-pressure (UHP) metamorphic zone in the Dabie orogenic belt. The study indicates that the crust under the Dabie orogenic belt has the features of the layer-block structure. According to the characteristics of the Poisson's ratio structure of the crust ,7,5 and 4 elastic blocks are distinguished separately in the upper, middle and lower crust from south to north along the Anyi-Zhuangmu profle. The principal suture zone between the Yangtze and North China blocks is an UHP metamorphic belt, the present boundary between the Yangtze block and the Dabie orogenic belt is the Taihu Lake-Mamiao fault which intersects with the Tanlu fault, and the Mozitan-Xiaotian fault is the northern boundary of the Dabie orogenic belt. The North Huaiyang tectonic belt plunges as a wedge downward into the upper and middle crust and its boundary with the North China block is the Feizhong fault. The Tanlu fault is subvertical in the middle and upper crust and dips to the west in the lower crust. The UHP metamophic belt is about 5 - 7 km thick and plunges toward the north beneath the northern Dabie block. The process of exhumation was tectonic emplacement rather than homogenous uplift. The main kinematic surface might be the Shuihou -Wuhe high-temperature shear zone.