The paper deals with the obtainment of microcrystalline celluloses which can be utilized as macromolecular support for some pharmaceutical compositions, for burns and atone wounds treatment. The utilised raw material is cotton cellulose, micronized by hydrolitic acid treatment. The influence of some factors on the yield and characteristics of the micronized product was as followed: acid concentration, temperature and duration of the process. The experimental results were computer processed, the functions correlating the properties analyzed with the hydrolysis parameters being thus obtained; on this basis, the optimal conditions for the hydrolytic treatment were established. The synthetized cellulosic powders were associated with antibiotics, antiseptics, with or without additives of steroid antiinflammators and trophics, pharmaceutical composition for burns and wounds treatments being thus obtained. Complex synergetic effects of regeneration, scaring and epithalization of wounds were observed.