The objective - of the research is to study the contribution of the genealogical constituent in the genesis of the formation of recurrent depressive disorders. A group of 108 patients with RDR who were in the main group and 46 persons without mental disorders who were in the comparison group were examined. To estimate the genealogical component, 297 relatives of the main group and 167 relatives of the comparison group were evaluated. The set of research methods included: clinical-psychopathological, clinical-genealogical and methods of statistical processing of the obtained data. A substantial accumulation of psychiatric disorders in the pedigrees of the patients with RDD was established, which indicates a significant role of hereditary factors in the occurrence of clinical forms of this pathology: the rate of relatives with mental disorders was statistically higher in the pedigrees of patients with RDR than in those in the comparison group (in the main group the rates of staying under observation by a psychiatrist and presence of depression in relatives exceeded 6-8 times, the rate of suicidal behavior 2.6-5.0 times, propensity to alcohol dependence 1.5-2.0 times (p < 0.05) similar rates in the comparison group. At estimation of gender aspects of hereditary burdening it has been established, that at increase of severity of DDR course the burdening of patients' family trees with mental disorders increased: the frequency of female relatives with depression (50.00 %) and male relatives with depression (20.00 %) and alcohol addiction (41.70 %) increased. The results indicate the need to consider heredity factors in the diagnosis, risk assessment of the severity of depression and its recurrence.