Exposed on the northern edge of North China Platform, Xilin Gol complex has an age of 1.3~1.0 Ga. It is mainly composed of hornblende-plagioclase gneiss and biotite-pla-gioclase gneiss, plagioclase-hornblende schist, and amphibolite. Subjected to metamorphism of hornblende subfacies, its protolith comprises mostly calc_alkaline igneous rocks. This paper deals with mineral chemistry of amphiboles and feldspars in the complex and indicates that the metamorphism took place at temperature of 540~550℃and pressure of 0.5~0.6 Gpa.