The invention discloses a flotation method for improving the recovery rate of low grade copper nickel ore. Procedures comprises a first section of grinding raw ore, a first section of rougher concentrate, a first section of rougher tailings, a first section of cleaner concentrate, a first section of cleaner tailings, a second section of rougher concentrate, a second section of rougher tailings, a second section of first cleaner concentrate, a second section of first cleaner tailings, a second section of second cleaner concentrate, a second section of second cleaner tailings, a second section of first scavenging concentrate, a second section of first scavenging tailings, a second section of second scavenging concentrate, a second section of second scavenging tailings, a final concentrate, and a final tailing dehydration. According to the method, useful ore is enabled to be separated from gangue; provided with suitable ore grinding fineness, gangue ore is removed to the largest extent; valuable metals such as nickel and copper are sufficiently recovered; copper nickel mixed concentrate which is qualified in concentrate grade is obtained; a rich oxygen top-blown smelting system is provided with qualified raw materials; the resource utilization rate is improved to a largest degree; and when the original nickel grade is 0.54%-0.62%, the nickel concentrate grade can reach 4.8%-5.0%, and the recovery rate of nickel can reach 65%-70%.