<![CDATA[Abstract. The polygamy permission case following an unregistered (siri) marriage in Surabaya Religious Court Decision Number 6357/Pdt.G/2021/PA.Sby arose because the Petitioner had first entered into a siri marriage with his prospective second wife and had a child, before filing for polygamy permission with the court. This raises questions on the decision's conformity with the monogamy principle under Article 3 paragraph (1) of Marriage Law No. 1 of 1974 and the principles of fiqh munakahat. This study aims to analyze the judge's legal considerations in the decision by referring to the Marriage Law and fiqh munakahat principles, to examine how the judge assessed the grounds, requirements, and benefit (maslahah) of polygamy filed afte r the siri marriage occurred. The research method used is normative juridical supported by an empirical approach, employing statutory, case, and conceptual approaches. The findings show that the panel of judges based its decision on juridical aspects, trial facts, and maslahah, including the first wife's consent, economic capacity, willingness to act justly, and legal protection for the child born from the siri marriage. The ground of biological needs raised by the Petitioner was not among the alternative grounds exhaustively regulated under Article 4 paragraph (2) of the Marriage Law, yet the petition was granted to prevent greater harm. This decision underscores the importance of legal certainty for wives and children, as well as compliance with marriage registration procedures. Abstrak. Kasus izin poligami pasca nikah siri di Pengadilan Agama Surabaya Nomor 6357/Pdt.G/2021/PA.Sby bermula ketika Pemohon telah lebih dahulu menikah siri dengan calon istri kedua dan memiliki seorang anak, sebelum mengajukan izin poligami ke pengadilan. Kondisi ini menimbulkan persoalan mengenai kesesuaian putusan dengan asas monogami dalam Pasal 3 ayat (1) UU No. 1 Tahun 1974 tentang Perkawinan serta kaidah fikih munakahat. Penelitian ini bertujuan menganalisis pertimbangan hukum hakim dalam putusan tersebut dengan merujuk pada UU Perkawinan dan prinsip fikih munakahat, guna mengetahui bagaimana hakim menilai alasan, syarat, dan kemaslahatan poligami yang diajukan setelah nikah siri berlangsung. Metode penelitian yang digunakan adalah yuridis normatif didukung pendekatan empiris, dengan pendekatan perundang-undangan, kasus, dan konseptual. Hasil penelitian menunjukkan bahwa Majelis Hakim mendasarkan putusannya pada aspek yuridis, fakta persidangan, dan kemaslahatan, mencakup persetujuan istri pertama, kemampuan ekonomi, kesanggupan berlaku adil, serta perlindungan hukum bagi anak hasil nikah siri. Alasan kebutuhan biologis yang diajukan Pemohon tidak termasuk alasan alternatif yang diatur secara limitatif dalam Pasal 4 ayat (2) UU Perkawinan, namun tetap dikabulkan atas dasar pencegahan kemudaratan yang lebih besar. Putusan ini menegaskan pentingnya kepastian hukum bagi istri dan anak serta kepatuhan terhadap prosedur pencatatan perkawinan. ]]>
