It has been established that the oxidation reaction of magnetite is the most important in a complex set of physicochemical processes accompanying the process of roasting magnetite iron ore pellets. Using derivatographic and mineralogical methods, the mechanism and kinetic parameters of oxidation on the generatrices from the Olkhovskiy magnetite and Kachkanarskiy titanomagnetite concentrates have been studied. The effect of the partial pressure of oxygen in the gas phase on the kinetics of oxidation is considered. From the temperature dependence of the oxidation rate at a given degree of conversion, the values of the apparent activation energy of the process are determined. The results of the work are of certain interest in optimizing the modes of low-temperature oxidation of iron ore materials (pellets) on a roasting conveyor machine.