Abstract: The Luming deposit lies in the southcentral block of the Xiaoxingan MountainsZhangguangcai Mountain polymetallic belt. Its major orebodies are hosted in the contact zones of the monzonitic granite and granite porphyry. The Mo ores occur in the quartz vein and distribute in the orebody with veinlet and stockwork shapes. The characteristics of the ore fluid inclusions trapped in quartz were studied deeply. The results showed that fluid inclusions in minerals are mostly vaporliquid (aqueous twophase) inclusions. The peak value of the homogenization temperature are 400， 220℃， respectively. The salinity of the fluid inclusions varies in 19%~144%. The average mineralization pressures are 18MPa， wheres the oreforming depths are in the range of 09~28km. The gas composition of the oreforming fluid are mainly CO2， H2O and CH4. Liquid composition are mainly Na+， Ca2+， SO2-4， Cl-. The fluid is mainly derived from the magma water， and a minor part from meteoric water mixed in the later. It is concluded that the Luming porphyry Mo deposit should be of hightomodtemperature hot liquid origin relevant to the acidintermediate intrusive magmation.

Key words: Luming Mo deposit, fluid inclusions, hydrogen and oxygen isotope, oreforming fluids, Heilongjiang