Abstract: Abstract: The studied glaucophane schist is in the Ordovician Halahahe Formation of Subugeta, Inner Mongolia, and there are a variety of rock assemblage types. According to the optical characteristics and EMP analysis, the authors have come to the conclusion that the glaucophane schist is a kind of ferriglaucophane in the study area. The topomineral assemblage of glaucophane schist is characterized by glaucophane + epidote + actinolite + phengite + sphene. The schist was cemented and recrystallized by shaly clasolite, and the formation environment of native rock was the marginal-sea basin of the continent. The metamorphic origin belonged to the regional low-temperature/middle-high pressure dynamic metamorphism related to plate movement.