Abstract: The Bayanhar gold deposit of Inner Mongolia is located in the northwest margin of Ailimiao-Xilinhot median mass in the northern margin of North China Plate. It is hosted in the sericite-quartz schist and chlorite schist of Wenduermiao Group, Mesoproterozoic. The formation of the deposit has a close relationship with Variscan magmatic activity and ductile shear zone in the region. Five orebodies are delineated, which are occurred as stratiform or lentiform and generally in NW direction, with ore types of quartz vein and mylonite altered rocks. The gold mineralization is closely related to silicification and beresitization. According to its geological characteristics, mineral composition, dissemination, wall rock alteration features and the former measurement of fluid inclusion temperature, it is concluded that the Bayanhar gold deposit genetically belongs to epithermal type.