Detailed study on process mineralogy of a skarn type copper-molybdenum ore from Jiama,Tibet is carried out with advanced MLA and electric probe as important assistant means,to find out the ore property,target mineral species,embedding grain size,composition and embedding relations,which are verified by ore-dressing experiments.The bulk flotation-copper molybdenum mixed concentrate re-separation process flowsheet is determined to be suitable to treat the ores and good test index is obtained.Investigation on the tailings from closed flotation circuit by MLA shows that the target mineral loss is within acceptable range.