ABSTRACT Here, transparent films were prepared from regenerated cellulose. Microcrystalline cellulose was solubilized in N,N-dimethylacetamide with lithium chloride. Exchange of organic solvent for water resulted in the gelation of solution. Transparent hydrogel served then for stable film preparation. No cellulose chemical modification and cross-linking was applied. To reinforce films, 5 wt% montmorillonite was added. Both pristine and modified clay was used. Modification was provided through intercalation by synthesized polyhedral oligomeric silsesquioxane (POSS) bearing eight amino groups. Examination of films with modified montmorillonite revealed its exfoliation for clay nanoparticles and POSS in the course of their preparation. In that case, a significant increase of tensile strength and elongation at break was observed, while a notable decrease of transparency for the UV part of the sun spectrum was also observed, which is important for the UV protection by cellulosic materials.