Abstract: In order to improve the recovery rate of target minerals，the flotation process was investigat⁃ ed for the problem that a large number of copper-containing intergrowths were circulated in the flotation sys⁃ tem due to the fine dissemination of useful minerals in a copper mine. The results show that the copper grade of concentrate in one stage roughing of series one is 18%~20%，which can be directly used as final concen⁃ trate; through the research on regrinding flotation test of concentrate in one stage scavenging，concentrate in two stage cleaning of series one and concentrate in three stage cleaning of series two，it is proved that the flo⁃ tation recovery rate can be increased by ten percentage points through regrinding flotation on middling of one stage scavenging，copper grade can be increased by three percentage points through pre-classification and regrinding concentrate on concentrate in two stage cleaning of series one and concentrate in three stage cleaning of series two. After the technological transformation of the process is completed，the two series of cleaning for scavenging tailings are directly transported to the ball mill pump pool，which can reduce the wa⁃ ter volume by about 300 m³，effectively reducing the impact on the roughing process. The concentrate grade is increased from 18% to about 20%，and the recovery rate is increased from 87.80% to 89.83%.

Key words: copper molybdenum ore, process optimization, flotation, middling regrinding