Abstract: The grinding process is a key link in the beneficiation process，which directly affects the disso‐ ciation effect of valuable minerals and the subsequent separation index. Taking the concentrated magnetic sepa‐ ration concentrate of a third stage grinding and classification system in a mine as the research object，aiming at the problems of high energy consumption，high steel consumption and serious overgrinding in the traditional steel forging grinding medium，the effects of three kinds of grinding media，steel forging，steel ball and porce‐ lain ball，on the indexes of grinding products were systematically discussed. Through laboratory tests，the parti‐ cle size distribution characteristics of grinding productd under different grinding parameters of grinding time， medium filling rate，grinding concentration were analyzed，and the grinding effect and energy consumption of each medium were compared. The results show that the grinding of ceramic balls is excellent in grinding rate and overgrinding control，especially the grinding effect of mixed ball diameter ceramic balls (ϕ25mm，ϕ20mm， ϕ15mm ratio of 5∶3∶2) is the best. The yield of -0.075 mm particle size is 87.64%，the degree of overgrinding is 31.67%，and the unit energy consumption is 27.43% lower than that of steel forging. In addition，the ceramic ball + steel ball mixed grinding scheme also shows good adaptability in dealing with emergencies. When the grinding concentration is 70% and the medium filling rate is 38%，the product particle size distribution of ce‐ ramic ball grinding is more uniform，which is beneficial to the subsequent magnetic separation operation. The research results provide theoretical basis and technical support for the optimization of mine grinding process， and show that it is feasible and economical to replace the traditional steel forging medium with ceramic balls.

Key words: grinding media, grinding parameters, negative cumulative production rate, energy con‐ sumption