To clarify the phase change at different reduction moments of 0， 5， 10， 20， 40， 60， 80 min and 110 min， the high-aluminium iron ore pellets were deoxidized in pure carbon monoxide at 950℃. The results show that there are three phases of iron， FeAl 2 O 4 and Fe 2 SiO 4 appeared after five minutes reduction. From 10 min to 110 min， the peak intensity of iron is becoming higher and the phase change of FeAl 2 O 4 and Fe 2 SiO 4 is unobvious. In addition， the reduction process of the ferric oxide in this iron ore does not well accord with the reduction law step by step be- cause of the earlier appearance of iron and the phases of Fe 3 O 4 and wustite undetected in the reduction process.