The establishment of the metamorphism and deformation stages of epimetamorphic clastic rock complex in orogenic belt will contribute to determining the forming mechanism of accretionary complex and constrain the accretion-exhumation process of oceanic crust subcution zone. Medium-or small-scale structure analyses on the Indosiniana ccretionary complex in the Mayigangri area of central Qiangtang suggest that the structural style is the coaxial superimposition of E W-trending simple shear deformation of Triassic subduction of oceanic crust and N S-trending compressional deformation during convergent stage, which was reformed slightly by the Cenozoic nearly N S-trending buckle folding on shallow tectonic level. The complex developed three distinct foliations which correspond to the above three stages, with the two earlier ones usually accompanied with epimetamorphism. The C-type foliation S1 of the first stage (M1D1) in the clastic rock is showed as penetrative syntectonic pressolution quartz veins on the regional scale. The microscopic temperature-measuring experiment for fluid inclusions found that a large amount of primary immiscible boiling inclusion groups occurred in the quartz veins and can be grouped into CO2-rich three-phase inclusions and NaCl-H2O solution two-phase (gas-liquid) inclusions. The both inclusions show a coincident complete homogenization temperature of 300~400℃ which represents the metamorphic temperature of the M1D1. The salinity-P/T isochore diagram of non-boiling gas-liquid two-phase inclusions shows a mean trapping pressure of 0.28 GPa, indicating the depth of the M1D1 is ~11.3 km. The prograde metamorphism of accretionary complex shows varied metamorphic facies series, with the shallow part of subduction channel characterized by medium P/T metamorphic facies series and the middle deep part feature high P/T metamorphic facies series. The exhumation retrometamorphic P-T-t paths of high-pressure metamorphic rocks exhibit as cooling type. Blueschists and eclogites exhumed into the epimetamorphic complex at late Triassic (211~221Ma), which was concurrent with the closure time of the paleo-Tethys ocean. After that, the transient convergence of North Qiangtang terrane and south Qiangtang accretionary terrane resulted in the second stage intense compressional deformation (M2D2) and syn-collision type intermediate-acid magmatism along the Longmu Co Shuanghu suture.