The birth of the Marriage Law No. 1 of 1974, especially the breakup of marriage has led to the dualism of Islamic law in Indonesia. Regarding Divorce on the one hand, Muslims are taught in Islamic fiqh that Divorce is the right of a husband, where if a wife is mentally ill even without a witness, then the divorce falls, while the marriage law in Indonesia, including the Islamic ummah, is specifically regulated in the Law Compilation Islam, determines that divorce can only be done before a religious court after going through a trial. Moreover, two Islamic organizations in Indonesia, namely Muhammadyah and Nahdlatul Ulama have different opinions. On the one hand, NU in the 28th Congress in Yogyakarta in 1989 gave a legal decision that Divorce was the husband's prerogative which could be dropped anytime and anywhere even without reason. If the husband has dropped divorce outside the Religious Court, then the divorce is valid. While the Majlis Tarjih Muhammadiyah in his fatwa that was tried on Friday, 8 Jumadal Ula 1428 H / 25 May 2007 M gave a ruling that divorce must be carried out through a court examination process, divorce carried out outside the court was declared invalid. The views of NU and Muhammadiyah above reflect a contradiction. Therefore the Indonesian Ulema Council based on the MUI IV 2012 Fatwa gave a fatwa as a middle way to resolve these differences with its fatwa that divorce outside the legal court is valid provided there is a syar'i reason that the truth can be proven in court. Iddah Divorce is calculated since husband drops divorce and for the benefit of benefit and guarantees legal certainty, divorce outside the court must be reported (ikhbar) to the religious court. With the Normative Juridical research method, the author tries to discuss the problem, namely trying to find the problems that arise as a result of these rules and find a way out how the MUI fatwa can be applied. From the results of the study, the authors conclude that the unrecognized Divorce legality outside the court causes legal chaos due to uncertain laws for the Islamic ummah, namely in terms of when the fall of divorce and the end of the iddah period, concerning triple divorce, concerning the validity of the status of children born after the fall Divorce and concerning the validity of the second marriage and the status of the child that was born which could damage the religion and descent of the Islamic ummah in Indonesia. If Marriage is legal according to the religion, then Divorce should also be valid if carried out according to the religious law. Factors that cause divorce outside the court include economic factors, juridical factors, sociological factors and customs factors, regarding the distribution of marital assets due to divorce outside the court, in general, the community resolves issues regarding marital property in a family manner by including local ulama and traditional leaders.