The Bameng antimony deposit located in southeastern Guizhou is a medium-size vein type deposit, with its orebodies controlled by the NE- and NNE-trending faults that belong to the subsidiary fractures of the Songtao-Rongjiang deep faulted zone. The present paper deals mainly with typomorphic characteristics of stibnite, the most important ore mineral in the deposit, in such aspects as chemical composition, physical property, optical propeity, crystal structure, isotopic composition and quartz inclusions, with a discussion given on the genesis of the Bameng antimony deposit. Typumorphic studies show that the stibnite is rich in Pb and poor in As, Hg and Ag，and its unit cell parameter a0 is larger than b0，attributed probably to the reason that Pb2+ has occupied some lattice sites of Sb3+ in a0 direction. Surfur and lead isotopic data have led the author to consider that the ore-forming materials were mainly derived from the wall rock--epimetamorphic rock of Xiajian Group. Fluid inclusion studies show that the ore-forming solution of the Bameng antimony deposit must have been a kind of meteoric hydrothermal solution with low salinity and weak acidity. It is therefore concluded that the Bameng antimony deposit is of meteoric hydrothermal vein type.