Abstract: There is 19.34% Fe in an extremely lean hematite ore from Anqian，iron mainly exists in form of hematite，with distribution rate of 89.90%.To develop and utilize the ore，high-intensity pre-separation experiment was carried out，influence of medium rob diameter，medium rob gap and magnetic field intensity on pre-separation index were investigated.Results indicated that，with feeding size of -3 mm，magnetic field intensity of 232.67 kA/m，medium rob diameter of 3mm，medium rob gap of 5 mm，pre-concentrate with iron grade of 25.07% and recovery of 85.99% was obtained，and discarding tailings with yield rate of 31.08% and iron grade of 9.06%.The results can provide reference for high efficient development of extremely lean hematite ore in our country.

Key words: Extremely lean hematite ore, High-intensity magnetic pre-separatiom, Magnetic medium