Abstract: Molybdenum commonly exists in low sulfide,it can form high ion or complex and dispersedly exists in intermediate-basic rock or acid rock,it also exits in black rock series and the efflorescence of Quaternary for absorbing by manganese iron strong material and organic material.It is easy to separate,move and gather,then formats magma gas liquid polymetallic deposit in high halide environment.Molybdenum distributes unusually in exposed area of basic volcanic rock,diamictite belt,black rock series and weathering area containing iron and manganese.According to the geochemical characteristics,geological chemical background of mineralize and metallogenic relation,we found sixteen forecast area in Yunnan Province.