Tongchang deposit is a very important copper deposit type in south of Shanxi province. Bystudying the geochemical feature of the deposit, we discuss the source of hydrothermal ore-form-ing solution and mineralization mass, and conclude the metallogenic model. The prototype ofspilite, which is the main outcropping stratum (Pt29 9O3~908Ma) in mine area, belongs to cale-alkaline volcanic suite. After Upper Proterozoic, the instrusive of Hercynian diorite brought gas-liquid, thermdynamic and some mineralization mass, formed the mixing hydrothermal solutionrich in CI, Na+ and K+ which mixed by magmatic hydrothermal solutinn and rain water. Themetallogenic elements in spilite and diorite were activated were by the mixing hydrothermal solu-tion and transported by Cl-complex and enriched mineralization in the endocontact and exocontactof diorite. The deposit belongs to low-to-mederate temPerature type which can be correlated withsubvolcanic rock.