Fluid inclusions were studied on the stratiform orebodies of the Woxi WSbAu deposit. Homogenization temperatures of aqueous inclusions in the quartz from the banded ores vary between 120℃ and 180℃, salinities between 2.9% and 8.9% NaCl eq. and density of the fluid between 0.94 and 0.96 g/cm3. REE geochemical compositions of the fluid inclusions indicate that the oreforming fluids were most probably derived from evolved seawater that acquired oreforming materials by circulating in the clastic sediment pile below the seafloor. When the oreforming hydrothermal fluids, which had a lower density than the ambient seawater, erupted into the overlying cold water column chemical and/or chemicalmechanical precipitation occurred in the ascending buoyant plume, resulting in the formation of stratiform orebodies. The range of homogenization temperature and salinity of the Woxi deposit is similar to that of many other SEDEXtype polymetallic ore deposits, implying a similar genesis for these deposits. The regular variation of the homogenization temperatures and salinities of fluid inclusions in quartz from a single ore beds or a single band of stratiform ores supports a syngenetic model for the Woxi WSbAu deposit.