Abstract: The key to realizing the high efficient pre-concentration of complex iron ore，improving the grade of grinding，simplifying the process of grinding and separation，reducing the quantity of grinding operation and lowering the production cost depends on separation equipment.NLCT series separator with external magnet for pre-concentration of complex iron ore developed by Beijing General Research Institute of mining and metallurgy has the external arc-type magnet and can realize the effective enrichment of high intensity magnetic minerals and low intensity magnetic minerals by axial sorting in cylinder.By using NLCT0607 type magnetic separator with external magnet，the pre-concentration of a low grade magnetite-specularite complex iron ore with particle size of 12～0 mm and Fe grade of 26.49% in Anhui Huoqiu area was made to realize the yield of tailing discharge 20.90% and the recovery rate of 92.35% Fe concentrate.The pre-concentration of vanadium-titanium magnetite with particle size of 10～0 mm，and Fe grade of 20.30% and TiO₂ grade of 7.88% in Panxi area also can realize the yield of tailing discharge of 25.92%，and Fe and TiO₂ recovery rate of 89.52% and 91.01% respectively.The industrial production index by using this series of equipment is close to the laboratory index.Therefore，NLCT series separator with external magnet has a broad application prospect in the efficient separation of complex iron ore.

Key words: Complex iron ore, Pre-concentration of coarse particle, NLCT series separator with external magnet