Abstract: The main useful mineral of the iron ore in Sichuan is magnetite．With deep mining of ore, the existing technological process is not suitable for the deep ore．The fineness of the second stage grinding is greatly reduced by adding the fine screen technology in the experimental study of the deep ore dressing process．The results show that the iron concentrate with the total iron grade of 60.24% and the total iron recovery of 88.67% can be obtained by adopting the beneficiation process of dry magnetic preseparation and discarding-two stage grinding, two stage magnetic separation and one fine screen of magnetic concentrate．