Yongxin Gold Deposit is located in the southern part of Duobaoshan Cu-Mo-Au metallogenic belt.To understand the genesis of the deposit and provide exploration insights,a study was conducted on the rare earth elements,micro-elements,and isotopic composition of gold-bearing pyrite.The results indicate that the chemical composition of pyrite shows enrichment in light REEs and depletion in heavy REEs,with a right-sloping REE distribution pattern.The pyrite is enriched in high-field-strength elements such as U,Th,Zr,and Hf,and depleted in large-ion lithophile elements like Ba and Sr.Ratios such as w(Hf)/w(Sm),w(Nb)/w(La),and w(Th)/w(La) suggest that the ore-forming fluid contained more Cl than F.A negative Eu anomaly and the absence of a Ce anomaly indicate that the ore-forming fluid formed under reducing conditions.Ratios like w(Y)/w(Ho),w(Zr)/w(Hf),and w(Nb)/w(Ta) suggest that the mineralization process did not involve external hydrothermal fluids,nor did metasomatism occur,with the ore-forming fluid closely related to both mantle and crustal sources.The sulfur isotopic characteristics indicate that the ore-forming materials originated from deeper sources.Genetic indicators such as w(Co)/w(Ni) and w(Fe)/w(S＋As) suggest that the deposit is of a meso-epithermal volcanic hydrothermal origin.Based on the magmatic origin,tectonic setting,diagenesis-mineralization age,metallogenic process,geochemical characteristics,and the main features of representative gold deposits in the region,it is concluded that Yongxin Gold Deposit belongs to a porphyry metallogenic system,forming during the Early Cretaceous as a meso-epithermal,relatively Cl-rich,weakly reducing gold deposit.