There is a significant difference between monogamous family and polygamous one, thus different family relationships are observed in each one. Whenever deep changes are found in the shape of family, style of residence, number of members in family in terms of their role and status, the content and degree of conflict in the family is directly affected. Never the less, all the theories used in this study insists on defining family as an intimate environment. According to these theories in polygamous families since different members should play the same role, they resort to competing mechanism to attain common, rare and valuable resources, either openly or in concealment. In this way, legitimacy is questioned, and a degree of conflict is created in power, emotional and sexual relationships in the family. To evaluate the hypothesis of the research, 300 women of which 150 belong to monogamous families and 150 are a member of polygamous families are studied through questionnaires and interviews. Finally, the hypothesis of this research which stated that there's a significant relationship between family structure and the content and degree of conflict in family relationships is empirically proved. As a result, conflict in power, emotional and sexual relationships in polygamous families that reside in the same house is most intensive, whereas conflict contained in power and emotional relationships of monogamous extended families is at average level.