Abstract: Use of N-dodecylethylenediamine (ND) in reverse flotation of hematite was investigated for separation of artificially mixed and actual iron ores. ND effectively separated quartz from hematite when the mass ratio of hematite to quartz was 1:1 and 3:2. At pulp pH of 7.27, 40 mg/L collector and 3.33 mg/L starch yielded product with 60.36% and 61.20% iron, respectively. In room temperature separation trials with actual ore, product containing 66.72% iron and a 93.46% iron recovery were obtained by subjecting iron ore at 95.42% -0.045 mm granularity in the presence of 200 g/t ND, 400 g/t sodium hydroxide, and 200 g/t starch to a coarse sorting, a fine sorting, and two scavenging operations.