Abstract: The utilization value of crystalline graphite concentrate in emerging strategic fields is determined by scale size and quality, but the scales are easily damaged during the crush and grinding process. How to effectively protect large scale is the key problem in the research of crystalline graphite mineral processing. The paper analyzes and compares the characteristics of the product and its influence of two crushing mechanisms of high-pressure grinding roller (HPGR) ultra-fine and ball mill (BM) coarse-grinding on the flake protection before roughing. Meanwhile, the study on the protection of graphite flake was compared with four types of vertical regrinding agitators such as helical screw, rotor disc, impellers and pins. It is pointed out that the combination of high-pressure grinding roller and vertical agitation mill will have a superior industrial application prospect in the graphite mine.