Fatigue syndrome, depression and cognitive function impairment are very frequent in multiple sclerosis. Investigations of symptoms of these disturbances were not examined routine. They require time and clinical experience. These sufferings can step out on every stage of the disease, also outdistancing physical symptoms, as well in clinically isolated syndrome. Unfortunately, they undergo remission seldom. Fatigue syndrome is one of the most frequent and the most serious problem in multiple sclerosis. It is the cause of serious motor and mental handicap and intellectual, the causing the greater depth the disability and deterioration quality of life. Moreover, it is unusually difficult to clinically effective treatment. The impairment of cognitive functions, and especially the fresh memory, belongs to deficits observed already in initial phase of disease. Depression among the patient with multiple sclerosis is result of many complicated processes. It can be result of chronicity of disease, as also the lack of possibility of effective treatment and the unforeseeable course of the disease or the effect of therapy of disease. Depression is intensified at the beginning of the disease, mainly in the relapsing-remitting form and influences on negative perceptions of neurological symptoms of the disease. It poorly correlates with clinical severity of multiple sclerosis. Fatigue syndrome, depression and cognitive function impairment more often were observed in primary progressive form of the disease than in relapsing-remitting, although this has not been a constant finding.