The Dongfengbeishan molybdenum deposit is located in northeastern Tianbaoshan ore concentration area in Yanbian Pre⁃fecture, Northeast China. Almost all discovered orebodies are controlled by faults and fractures in biotite quartz diorite, and character⁃ized by veins and veinlets. The deposit experienced three metallogenic stages, namely quartz-molybdenite stage, quartz-polymetallic sulfide stage and quartz-calcite stage. Fluid inclusions in ore-bearing quartz veins can be classified into liquid-rich phase, gas-rich phase, daughter mineral-bearing three-phase and minor CO2-bearing three-phase occasional pure CO2 inclusions. Fluid boiling oc⁃curred during ore-forming evolution and might have played a very important role in metal elements precipitation. Besides H 2O va⁃ por, the gas phase in different types of inclusions, analyzed by Laser Raman Spectrum, also contains small amounts of CO 2 and CH4, which indicates that the ore-forming fluid belongs to the H2O-NaCl±CO2±CH4 magmatic fluid system with medium-high temper⁃ature and medium-high salinity. The discovered vein molybdenum orebodies in the Dongfengbeishan molybdenum deposit resulted from the porphyry molybdenum mineralization, which implies that the metallogenic porphyry intrusion should have occurred under the biotite quartz diorite. The veinlet disseminated molybdenum mineralization has important guiding implications for further theoret⁃ical research and geological prospecting.%东风北山钼矿床位于延边天宝山矿集区东北部，已探明的浅部石英脉型钼矿体均受黑云母石英闪长岩中的构造裂隙控制，经历了石英—辉钼矿阶段、石英—多金属硫化物阶段和石英—方解石阶段。含矿石英脉中主要发育富液相、富气相、含CO2三相、含子矿物三相和少量纯CO2五种类型包裹体。石英—辉钼矿阶段包裹体类型多样，且具有相似的均一温度，表明流体演化的过程中发生了沸腾作用，流体沸腾是导致Mo元素沉淀富集成矿的主要机制。包裹体气相成分除H2O以外还含有部分CO2和少量的CH4，表明成矿流体属于中高温、中高盐度的H2O-NaCl±CO2±CH4流体体系。综合分析认为，该矿床已探明的脉型矿体应属斑岩型钼矿成矿作用的浅部结果，含矿黑云母石英闪长岩体的深部或外围应存在成矿斑岩体，其中细脉浸染型钼矿化是进一步研究和地质找矿的重点。
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