Abstract: Magnetic roasting-magnetic separation process is considered as a feasible solution to separate iron mine. Because of its characters of low-pollution, widely distributed and resource-rich, biomass can be transformed in a thermochemical way to reductant applying in magnetizing roast. This research utilizes hematite and straw biomass to carry magnetization roasting experiment. Under conditions of 750 degrees C, roasting time of 7.5 min, iron ore and biomass dosing of 10:2, pure nitrogen with 300 mL/min, this research acquires index of iron concentrate with grade of more than 71.0% and recovery of more than 99.5%. Test results of XRD, VSM, SEM show that specific diffractive peak of hematite transforms into specific diffractive peak of magnetite, while magnetic moment per unit mass reaches more than 1 500 A·m²/g and the maximum of special magnetization coefficient achieves 0.26×10^-3 m³·kg^-1. It verifies the feasibility of straw biomass as a magnetized roasting reducing agent, providing an effective solution to utilization of straw and iron resources.