Abstract: The Nanwenhe metamorphic core complex is located near the China-Vietnam boundary, in Yunnan province. It consists of two parts, the metamorphic core and cover, which are divided by a sole peel fault. The complex is a component part of the metamorphic core complex belt on the west margin of the Yangtze platform. The study of the metamorphic core complex has important significance for the understanding of the crustal evolution and mineral exploration in southeastern Yunnan.