Polygyny is one of the types of marriages that was practiced in both Jahiliyya Arabs and Muslims as well as in many societies in the history. There is no doubt that there were social, political, cultural, economical, psychological, and geographical reasons for practicing that kind of marriages. When we look at the time of Jahiliyya and time of emergence of Islam, we can see that conditions that gave rise to polygyny and its application in both society were similar in general. It has to be noted that this type of marriage was not common in both societies. On the other hand, it should not be forgotten that polygyny was being practiced by the people who had higher status and rich. There were several reasons for practicing polygyny. Some of them are; desire to have more sons, to resolve conflicts among tribes between opponents to the new religion (Islam) and Muslims, to improve political and social relationship, to build social security for women.