The Mianlue tectonic zone is located in the southern Qinling orogenic belt. It is a complex ophiolite mélange belt formed by an Indosinian collision between North China and Yangtze Plate, superimposed with late intracontinental deformation. It is of great value to understand the tectonic processes of the Qinling orogenic belt. In this paper, through detailed structural analysis and paleostress inversion, it is revealed that Mianlue tectonic zone experienced three stages of structural deformation: the D1 stage was NW—SE compression, characterized by tight syncline fold with vertical axial plane and high angle reverse fault, which were formed in the collision between North China and the Yangtze in Early—Middle Triassic. The D2 stage is NE—SW compression, mainly developed left strikeslip shear deformation, superimposed on the early deformation structure track. The nearly horizontal stretching lineation of E—W direction is generally developed in the structural belt, and locally developed vertical folds formed in the Late Triassic to Middle Jurassic. In this stage, the Qinling orogenic belt transformed from early collision to intracontinental deformation, and largescale left strikeslip occurred along the E—S trending fault belt. The D3 stage is N—S compression. Under the multidirectional convergence structure system from Late Jurassic to Cretaceous, the Mianlue tectonic zone was compressed in the N—S direction, forming a series of conjugate shear faults, cutting the early deformation. The Dabashan Mountain and Western Qinling on the north side were thrust to the south, the northern margin of Yangtze Plate wedge into Qinling orogenic belt along the Micangshan area, forming a southward protruding Dabashan arc thrust nappe structural belt, WuduZhouqu arc structural belt in the western Qinling, and a series of NE and SW trending conjugateshear faults.