Celestite ore (SrSO4) is used as raw material for the production of strontium compounds. The aim of this study is to develop a new and efficient strontianite (SrCO3) production method. Strontianite was obtained from domestic celestite concentrate with direct conversion method in which celestite reacts with CO32- and NH4+ containing solution. Thus, the effect of particle size, time, ammonia concentration on the conversion was investigated. (NH4)(2)CO3 solution was used as carbonate agent. Because the solution is decomposed at 58 degrees C, experiments were performed low temperatures. Celestite ore was converted to strontianite between 3 and 6 h depending on ammonia concentration and celestite mass. Characterization of celestite ore, products and reaction residues were carried out by DSC, TG, XRD, and AAS analytical techniques.