Abstract: In order to solve the problems of long process and high grinding energy consumption in the existing production process of Gongchangling Concentrator，a high pressure roller crushing-wet preconcentration test was carried out. The results show that under the optimal conditions of roller surface spacing of 10 mm，roller surface pressure of 10.5 MPa，roller surface speed of 14 r/min，feed particle size of -3 mm and magnetic field strength of 240 kA/m，the technical indexes of total iron grade of 36.30%，tailings throwing rate of 31.84% and iron recovery rate of 88.19% can be obtained. This process can improve the processing capacity and iron concentrate production of the concentrator，which is of great significance to improve the economic benefits of the enterprise.

Key words: high pressure roller mill, crush, wet pre-separation, iron ore