Abstract: This article is focused on the reduction law of Indonesia ironsaud oxidized pellets by hydrogen. Reduction experiment was performed with a thermogravimetric analyzer. The hydrogen reduction mechanism of the oxidized pellets was studied by the phase change, thermodynamic and kinetic analyses of the reaction process. It is found that the final products are FeTiO₃ at 800℃ and 850℃, and the restrictive step of reduction is composed of two different stages, which are chemical reaction in the early stage of reduction and the mixed-control of chemical reaction and intraparticle diffusion in the subsequent reaction. Titanium oxide appears at 900, 950 and 1000℃, and the restrictive step of reduction is composed of three stages, which are chemical reaction, the mixed-control of chemical reaction and intraparticle diffusion, and intraparticle diffusion.