The results of comparative clinico-epidemiological study of schizophrenic patients in the three populations differing in their socioeconomic and cultural conditions allowed us to identify the disease characteristics determined by general pathogenic mechanisms (relationship of initiation and prevalence of one or another course types with age and sex of the patients) and characteristics liable to changes under impact of social factors (the prevalence of the disease, its representation in different age groups. Relationship of the forms of its course, syndromological structure, clinical features, nature of social and labor adaptation). Migration, cultural features, socioeconomic level of the region, educational level are stressed among the factors influencing the incidence of schizophrenia, its course and social and labor adaptation.