An aim of the study was to investigate a relationship between global and local brain atrophy with neurological impairment (motor dysfunction) in multiple sclerosis (MS) patients with different levels of disease severity. Fifty five patients with definite MS (Mc Donald's criteria), aged 18-60 years, disease duration 1-30 years, and 25 healthy age-matched controls have been studied. Neurological assessment (Kurtzke and EDSS scales) was performed in the all patients. The patients were divided into 3 groups: EDSS<3.5 mild disability, EDSS 3.5-6.0 moderate disability, EDSS>6.0 severe disability. In MS patients, the global brain atrophy was accompanied by the local atrophy of subcortical structures (thalamus, basal ganglia) and cerebellum. The processes of cerebral grey matter total and local atrophy were not similar. The progression of MS, neurological impairment is accompanied by the cerebellum and lentiform nuclei atrophy. There was the decrease of brain parenchyma volume, nucleus caudate and cerebellar local atrophy in patients with moderate disability. The severe disability was correlated with the thalamic atrophy and marked basal ganglia and cerebellar atrophy. Thus, we can suppose that the thalamic atrophy is important for the development of severe motor dysfunctions in MS patients.