Abstract: By means of optical microscope identification and electron probe analysis,the ore characteristics and gold occurrence state of Yanliweigou Gold Deposit were studied.The metallic minerals in the ore were mainly pyrite,followed by arsenopyrite and stibnite.The gold mineral is mainly native gold followed by electrum.The gold is dominated by fine-grain gold followed by micro-grain gold and mediumgrain gold and there is a small amount of submicroscopic grain gold;the shape in which gold is embedded is mainly pointed grain,lamellar,veinlet;the occurrence state is dominated by fissure gold and intergranular gold followed by encased gold;the gold-bearing minerals are pyrite,quartz,limonite,arsenopyrite and carbonatite.Pyrite electron probe analysis shows that the Yangliweigou Gold Deposit was formed in a medium-low temperature environment,and is related with magmatism;Based on the gold enrichment in the strata of the area and its peripheral Devonian and Carboniferous systems,it is believed that the metallogenic materials in Yangliweigou Gold Deposit may be a mixed source of strata and magma.