Lithium ferrite, LiFeO2, has attracted considerable interest due to its potential industrial applications, for example, as a cathode material in lithium rechargeable batteries because it has lower toxicity and cost, relative to LiNiO2 and LiCoO2 [1]. In most of cases it is necessary to obtain a nanostructured LiFeO2, which can be achieved by using lower synthesis temperatures. It is known, that one way to prepare powdered materials in a highly dispersed state and with disordered structure is the use of the mechanical activation in high energy ball mills. Mechanically activated powders are highly reactive and therefore the final products at lower temperatures and durations of thermal treatment could be obtained. In this work, the effect of mechanical activation of Fe2O3-Li2CO3 initial reagents on LiFeO2 synthesis was investigated by XRD and TG/DSC analysis. The powders mixture was dry milled in air using an AGO-2S planetary ball mill with stainless steel balls and vials for 60 min. The powder to ball mass ratio was 1:10. Thermogravimetric and calorimetric (TG/DSC) measurements were carried out by simultaneous thermal analyzer STA 449C Jupiter (Netzsch, Germany) in a nonisothermal mode within a temperature range of (20-900)°C. Phase compositions of ferrite were determined by X-ray diffraction analysis using ARL X’TRA diffractometer with СuKα radiation. The Powder Cell 2.4 software was used for a full-profile analysis of XRD patterns. XRD analysis showed that for mechanically activated powders, a decrease in the intensities and an increase in the half-width of superstructure reflections for α-Fe2O3 were observed. According to TG analysis, a preliminary mechanical activation of initial reagents leads to increasing the reactivity of the solid state system, which is to lower the temperature of LiFeO2 synthesis onset. The shape of DTG curves is similar to that of DSC curves, which shows that the mass changes can be attributed to the observed endothermic effects. The results obtained are consistent with earlier results for lithium-substituted ferrites formation from mechanically activated initial reagents [3].