The Changlingjian deposit is a newly discovered tungsten polymetallic deposit, which located in the eastern sector of the Jiangnan tungsten belt (JTB). The Re-Os dating of molybdenite in the Changlingjian deposit yielded a weighted average age of 133.8±1.3 Ma, indicating the mineralization is genetically related with the coeval muscovite granite beneath the deposit. After detailed geological and petrographic characteristics, we subdivided the mineralization process from W-sulfide-quartz (stage I), sulfide-quartz (stage II) to calcite-quartz (stage III). The temperature and salinity calculation results of the three-stage fluid inclusions show that, there are decreasing temperature and salinity degrees from stage I (281~386℃,0.70～10.11% NaCl_eq), stage II (186~317℃, 0.70~4.03% NaCl_eq) to stage III (156~202℃,0.70~2.07% NaCl_eq). The δ³⁴S values of sulfides from stages I and II range from -4.5‰ to 2.8‰. Mineralized coexisting quartz fluid inclusions (Stage I and Stage II) δ D ranges from -70.3 ‰ to -58.3 ‰, and the δO H2O value obtained from the conversion of O quartz in quartz ranges from -0.1 ‰ to 4.8 ‰. Those isotopic characteristics infer that the ore-forming fluid was dominantly from magmatic fluid with some meteoric water added, and increasing meteoric water ratios during the fluid evolution. The precipitation of tungsten in the Changlingjian deposit is mainly controlled by fluid immiscibility, while the precipitation of sulfide minerals is mainly controlled by fluid mixing. Combined with reginal ore-forming fluids research, the ore-forming fluid in Changlingjian deposit has similar character with most tungsten deposits in JTB, which were consistently source from ore-forming granitoid intrusions, with mixing a small amount of meteoric water.