Abstract:Two single particles size distributions such as 0.83~2 mm、0.35~0.83 mm of Panzhihua vanadium-titanium magnetite were used, Steel balls and short cylindrical steel forgings as grinding medium ,the grinding conditions as follows：pulp concentration of 80%, grinding time of 0.5、1、2、4、6、8、10 min, mill speed of 96 rpm/min, steel ball proportion with D30：D25：D20=42：60：93, short cylindrical steel forgings proportion with D30×30：D25×25：D20×20=28：40：62,ball charge of 40%. The results show that the comminution of vanadium-titanium magnetite with different medium shapes obeys first-order-breakage kinetics , and the specific rates of breakage of the short-cylinder steel forging were obviously higher than the steel ball under short time, also there has significant effect on primary breakage distribution parameters with the shape of the medium.