Abstract:A certain copper ore in Chacarilla area from Bolivia, with the high Cu content of 2.74%, belongs to one type of high grade and high mud content complex copper oxide ore. In order to make full use of the ore, the raw ore was classified and pre-discarded by 0.18mm., the barren rocks, which accounted for 47.03% of the raw ore (－0.18mm size fraction), could be pre-discarded, while the copper loss of less than 10%, the Cu grade of the feed of flotation (＋0.18mm size fraction) was increased to 4.65%, the treatment capacity can be effectively improved and the flotation environment can be significantly ameliorated. The oxidation rate of Cu of the feed is 83.18%, in which the "non-floatable " bound copper accounts for 10.93%, the main gangue minerals in the feed of flotation are quartz, feldspar, calcite and muscovite and so on, the copper minerals are mainly hematite, copper alum and a small amount of malachite, chrysocolla and digenite, which would increase the difficulty of flotation. According to properties of the feed, the flotation was carried out. The results show that, under the optimum conditions, concentrate with the Cu grade and recovery of 25.76% and 89.36% respectively, could be obtained by activation flotation process of “step by step flotation of easily and difficultly flotation minerals”.