The reduction process of the low silicon magnesium pellet at 900 ℃ under pure CO atmosphere was investigated, and the phase composition and microstructure of pellets at different reduction temperatures were also examined by X-ray diffraction (XRD) and mineral microscope. The results show that the reduction order of Fe₂O₃ was Fe₂O₃→Fe₃O₄→FeO→Fe. When the reduction degree increased from 0% to 10%, Fe₂O₃ was reduced to Fe₃O₄ and the pellets were uniformly reduced from outside to inside. When the reduction degree increased from 10% to 50%, Fe₃O₄ was reduced to FeO and the phenomenon of reductive aggregation occurred. The reason for above is that the internal pore distribution of the pellets is not uniform, subsequently, most of the FeO was reduced to metal Fe. The reduction order of MgFe₂O₄ was MgFe₂O₄→Mg_0.239Fe_0.761O→Mg_0.64Fe_2.36O₂→Fe, and the reduction started when the reduction degree of pellets arrived at 30%. The reason for this phenomenon is that MgFe₂O₄ is more difficult to be reduced than Fe₂O₃. The kinetic analysis by using the unreacted nuclear model indicate that the pellets reduction were controlled by the interfacial chemical reaction at the early stage, but the later reduction process was neither controlled by the internal diffusion nor the mixed control.