Abstract. This research is entitled "Review Of Fikih Muamalah Akad Bai 'On Mystery Box Selling Practices On The Site Of Tokopedia". It aims to answer the question of how the practice ofbuying and selling in mystery box terms of fiqh muamalah contract bai. The benefits can be a guide for the community and government in making fellowship. A qualitative approach is used by observation, interview and documentary techniques. The research was conducted with AlamLestariCell, Alvaroaccshop and TokTok Store as well as buyers who gave their responses after buying the mystery box. The results of the study conclude (1) the concept of fiqh muamalah akad bai ' refers to a buying and selling relationship based on the concept of halal and haram, justice based on the concept of Islamic economics which is in accordance with muamalah principles as well as existing terms and conditions, with mutual enthusiasm and avoidance. from costly loss. (2) The practice of buying and selling mystery boxes is carried out by the buyer selecting a product andprice mystery box  with very limited information on the goods inside, and making a payment until it is confirmed, then the seller chooses the goods to be sent randomly (random). (3) Based on the results of the fiqh muamalah akad  bai 'review, the description of the goods in the box is not clearly known (gharar) and the price of the mystery box is quite expensive (gharar katsir), as well as the disappointment of some buyers (dzalim), the selling practice buying mystery box is prohibited.Keywords: Mystery Box, Tokopedia, Gharar, prohibitedAbstrak. Penelitian ini berjudul “Tinjauan Fikih Muamalah Akad Bai’ Terhadap Praktik Mystery Box di Situs Tokopedia”. Bertujuan menjawab pertanyaan bagaimana praktik jual beli mystery box ditinjau dari fikih muamalah akad bai. Manfaatnya dapat menjadi panduan bagi masyarakat dan pemerintah dalam bermuamalah. Pendekatan kualitatif digunakan dengan teknik observasi, wawancara dan dokumentari. Penelitian dilakukan kepada AlamLestariCell, Alvaroaccshop dan TokTok Store serta pembeli yang memberikan tanggapan setelah membeli mystery box. Hasil penelitian menyimpulkan (1) konsep fikih muamalah akad bai’ mengacu pada hubungan jual beli yang didasari oleh konsep halal dan haram, keadilan berdasarkan konsep ekonomi Islam yang sesuai dengan prinsip-prinsip muamalah serta syarat dan rukun yang ada, dengan rasa saling rido dan terhindar dari rugi merugikan. (2) Praktik jual beli mystery box dilakukan dengan  pembeli memilih produk dan harga mystery box dengan informasi barang didalamnya yang sangat terbatas, dan melakukan pembayaran hingga terkonfirmasi, selanjutnya penjual memilihkan barang yang akan dikirim secara acak (random). (3) Berdasarkan hasil tinjauan fikih muamalah akad bai’, deskripsi barang dalam box tersebut tidak diketahui secara jelas (gharar) dan dengan harga mystery box yang cukup mahal (gharar katsir), serta adanya kekecewaan dari beberapa pembeli (dzalim), maka praktik jual beli mystery box ini dilarang.Kata Kunci: Mystery Box, Tokopedia, Gharar, dilarang