Based on mineralogical composition of Filizchay polymetallic ore and its mechanical strength optimum conditions of its grinding have been determined for further processing. It has been found out that after four-time crushing the particles of sizes +0.25–5.0 mm make ~80% of the material. Milling of produced particles in a ball mill showed that at the amount of loaded material equal to 1.0–1.5 kg and the duration of time 50–60 min the output of conditioned class of ore particles is found to be 98.5%.