Abstract: The bottlenecks encountered in the operation of the plant′s flotation system are ageing of equipment, low operating performance and high consumption of reagent. Identifying these problems, work is made on renovation and upgrading of the flotation system proceeding from the following 3 aspects for effecting high-efficiency flotation and reduction of feed volume: use of high-efficiency fine-aperture screen plate on vibrating sieve bend, enlargement of the size of underflow orifice of classification cyclone, and change of coarse slime centrifuge basket in strict accordance with the set rule. Operation with the upgraded flotation system has led to increase of tailings ash from 60.97% to 71.10%, rise of concentrate yield from 88.90% to 89.27%, up by 0.37 percentage point, drop of oil consumption from 0.196 kg/t to 0.170 kg/t, a decrease of 0.026 kg/t, bringing about an annual economic yield of 3.612 3 million yuan for the plant.