Abstract: In order to understand the ore washability of the deep VI ore body of Chengchao Mine and the adaptability of the existing beneficiation process，the ore washability test of VI ore body is carried out. The test results show that the main useful minerals in the ore of VI ore body are magnetite and associated pyrite，and the gangue minerals are mainly quartz and feldspar.Compared with Ⅴ ore body，the dissemi‐ nated particle size of the useful minerals is fine. The iron concentrate with yield of 34.50%，iron grade of 67.70% and iron recovery of 81.89% can be obtained by using the pre-discarding-stage grinding-stage separation process. The separation effect is good，and the concentrate product meets the index requirement of iron grade of more than 67.5%. The ore of VI ore body has good separability and can adapt to the exist‐ ing separation process.

Key words: magnetite, process mineralogy, grinding fineness, magnetic separation