Kinetic characteristics of oxidation of samples prepared form Ol’khovka magnetite and Kachkanar titanium-magnetite concentrate, and also of fluxed and nonfluxed pellets from Kachkanar ore at moderate and high temperatures, were determined by physicochemical analysis using experimental techniques. The method for determining the completeness of oxidation processes was developed. Dependences of the effective oxygen diffusion coefficient on temperature were obtained for fluxed and nonfluxed pellets. The effective diffusion coefficients of oxygen in pellets roasted in the isothermal and non-isothermal heating were found to be almost identical. The temperature ranges were found in which the basicity of the pellets has a negligible effect on the oxygen diffusion. Using the kinetic dependences of the isothermal oxidation of the studied materials, the effective activation energy at the given oxidation completeness values was calculated. Obtained results are of interest for specialists searching for the optimal parameters of roasting of magnetite pellets in conveyor lines. They may help to decrease the specific fuel consumption during roasting and achieve an economic gain.