[Skripsi ini membahas pembatalan perkawinan poligami karena ketiadaan izinisteri pertama dalam melakukan poligami. Pasal 5 UU Perkawinan, Hukum Islamdan Pasal 58 KHI (ijtihad para ulama Indonesia), mengatur bahwa poligamidiperbolehkan apabila memenuhi syarat-syarat. Dalam melakukan penelitian,penulis menggunakan metode penelitian kepustakaan yang bersifat yuridisnormatifdan tipologi bersifat deskriptif analitis. Permasalahan dalam skripsi iniadalah bagaimana pengaturan pembatalan perkawinan poligami, bagaimana akibatpembatalan perkawinan poligami dan apakah tepat pertimbangan hakim dalampembatalan perkawinan pada Putusan Pengadilan Agama Tangerang Nomor312/Pdt.G/2009/PA.Tng. Kesimpulan atas permasalahan tersebut adalahperkawinan poligami yang dilakukan tanpa adanya izin isteri pertama adalahbertentangan dengan UU Perkawinan dan KHI sehingga dapat dibatalkan. Putusanpembatalan perkawinan menyebabkan perkawinan mereka batal, mereka bukanlagi sebagai suami isteri, hak dan kewajiban antara suami isteri menjadi hapus,tidak ada harta bersama, anak yang lahir dari perkawinan yang dibatalkan tetapmenjadi anak sah dari kedua orang-tuanya dan ada masa iddah bagi isteri. PutusanHakim PA Tangerang Nomor 312/Pdt.G/2009/PA.Tng sudah tepat., This thesis examines the annulment of marriage caused by the absence ofpermission from the first wife to do polygamy. Article 5 of Marriage Law, IslamicLaw and Article 58 Compilation of Islamic Law (ijtihad by Indonesian muslimscholars), regulate that husband is permitted to do polygamy if he fulfill therequirements. In conducting this research, the writer uses juridicial-normativelibrary research methods and the typology is descriptive analytical. The problemin this thesis are how is the regulation of polygamous marriage annulment, theconsequences of polygamous marriage annulment and whether the judgessentence of religious court of Tangerang No. 312/Pdt.G/2009/PA.Tng is alreadyappropriate and correct or not. The conclusion of those problems are polygamousmarriages that held without the first wife’s permission is prohibited and againstMarriage Law and Compilation of Islamic Law, so that polygamous marriage canbe annulled. Polygamous marriage annulment causes their marriage is annulled,they are no longer as husband and wife, the rights and obligations betweenhusband and wife whose marriage is annulled become no longer exist, there is nocommon property between them, children who were born on that annulledpolygamous marriage are still legitimate child of their parents and there is waitingperiod for the wife. Judge’s sentence of Religious Court of Tangerang No.312/Pdt.G/2009/PA.Tng is correct and appropriate.]