Polygamy is not a rare form of family and marriage relations in the modern world, but it has become a revived reality in response to the challenges for Dagestan society of the modern era and the crisis in Russia. This issue attracts public and scientific attention by the inconsistency of practice of polygamy in Dagestan society. On the one side, the majority of the republic’s residents perceived this process negatively and, on the other, polygamy entrenched in the system of family and marriage relations steadily. Why is this happening? There are issues of the harmonious implementation of the ideology of polygamy in Dagestan society from the point of view of the historically established tradition of polygamy and the future of polygamy institution in Dagestan taking into account the results of the author’s sociological survey of residents of the republic (N = 507) in this article, authors take into account the geographical position of Dagestan as northern, plain and southern zones of the republic and gender and age characteristics of the population, and level of education, religiosity, marital status and type of settlement. Authors concluded that polygamy in Dagestan largely deviates from the norms and principles of polygamy in the Muslim tradition, because of which the distorted form of polygamy becomes unacceptable even for the truly believing part of the population, accepting as norms Islam practice of polygamy. The practice of polygamy developing in this logic has a most destructive effect on the traditional institution of the family in Dagestan, generating the dynamics of divorce and consolidating the destructive vector of the development of family and marriage relations.