Abstract: The Wencang copper deposit is located in the central and southern part of the Lancang River fault in the Sanjiang orogenic belt. The region has undergone multiple tectonic movements. The com⁃ plex geological tectonic environment and rich provenance provide favorable conditions for mineralization. It is a typical copper deposit produced on the west side of the Lancang River fault.By systematically studying the core contents of regional metallogenic background and geological characteristics of the deposit，the for⁃ mation mechanism of the deposit is preliminarily clarified and its genetic type is determined.The research shows that the main body of Wencang Copper Mine is located on the west side of the Lancang River fault， which is controlled by the Dashitou fault and the Kejie fault.The ore body occurs in the F3 fault fracture zone in the metamorphic rock of the lower section of the Pingzhang formation (C1pn1 ) of the lower Carbonif⁃ erous system，which is strictly constrained by the distribution law of the NW-trending secondary fault frac⁃ ture zone.The ore body is vein-like with good grade and thickness stability. The ore develops a semi-auto⁃ morphic-allotriomorphic irregular granular structure，and the structural types are mainly disseminated and veinlet disseminated.In summary，it is determined that the genetic type of the deposit is a medium-low temperature hydrothermal fissure filling metasomatic copper deposit.The research results provide an impor⁃ tant geological basis for the prospecting and exploration of similar copper deposits in the region.

Key words: copper deposit, structural ore-control, medium-low temperature hydrothermal, copper de? posit, clue for prespecting