OBJECTIVE To study an effect of the protein-peptide preparation cellex on the cerebral tissue processes in case of parenchymal hemorrhage breed under experimental conditions. METHODS The research involved the morphological examination of fragments of cerebral tissues of 57 rabbits of Chinchilla breed in artificially-provoked hemorrhagic stroke. Animals were divided into 2 groups: the first group received cellex once a day during 10 days, the second group received physiological solution in the same doses. The cerebral tissue was examined macroscopically and with histological, immunocytochemical and morphometric methods with subsequent data analysis. CONCLUSIONS A much more pronounced regression of the neurological deficit was observed in the group of animals which were administered cellex. There was a significant increase in volume of active movements in the limbs. No connective tissue changes were observed macroscopically in rabbits of the first group. Besides, the area of destruction decreased in size in comparison with initially diagnosed one. A decline in the rate of the formation of connective tissue was observed in damaged parts of the brain. The microscopic study of the first group showed that the degree of inflammatory and hemodynamic disturbances was much lower and necrosis foci were not detected, however small foci of neoangiogenesis were found.