This study aims to find out how the sociological purpose of polygamy in the perspective of Christianity itself in social life knowing that based on Christianity itself polygamy is prohibited, it does not mean that there is no polygamy in Christianity, but if you look at it historically in the Bible which divided into two parts, namely in the old agreement and the new agreement there are several explanations about how polygamy can exist and then become a prohibition. The type of research used is empirical law (sociological), using legal research material sources consisting of primary law and secondary law. The technique of collecting legal materials is done by interviewing and observing. then processed based on the topic of the problem that ...