Busana Melayu merupakan representasi kultur dan budaya Melayu dalam bidang berpakaian, memiliki nilai simbolis khas Melayu yang sarat makna dan dipakai sesuai dengan kondisi, waktu, maksud dan tujuan. Nilai-nilai budaya dan keagamaan menjadi ciri khas busana pengantin Melayu Tamiang harus tetap dipertahankan dalam perkembangan busana pengantin Melayu. Tujuan dari penelitian ini untuk mengidentifikasi dampak positif dan negatif asimilasi, perkembangan gaya busana pengantin Melayu, dan eksistensi busana pengantin Melayu di Desa Medang Ara Kecamatan Karang Baru Aceh Tamiang. Jenis penelitian merupakan deskriptif kualitatif dan pengumpulan data dilakukan melalui observasi, wawancara dokumentasi dan triangulasi. Teknik analisis data melalui reduksi data, penyajian data dan kesimpulan/ verifikasi. Hasil penelitian menunjukkan asimilasi di Aceh Tamiang tidak hanya disebabkan oleh keadaan masyarakat yang multietnis, namun banyak faktor yang mempengaruhinya diantaranya sikap toleransi masyarakat, keterbukaan masyarakat terhadap hal baru, dan pernikah campur dengan suku lain (amalgamasi). Asimilasi menyebabkan masyarakat kurang memahami budaya sendiri, sehingga mengubah pandangan masyarakat terhadap busana adat pengantin. Calon pengantin dalam memilih busana pengantin tidak berdasarkan kebudayaan yang dimilikinya, melainkan berdasarkan trend dan nilai estetika. Tolak ukur masyarakat dalam memilih baju adat bukan berdasarkan nilai-nilai kebudayaan yang ditampilkan. Namun, beberapa responden tetap mempertahankan tradisi dan menggunakan busana pengantin Melayu secara autentik dengan mengedepankan nilai-nilai kebudayaan. Hasil penelitian ini dapat memberikan gambaran tentang perubahan tren busana pengantin Melayu dan implikasi dari asimilasi budaya terhadap keberlangsungan budaya Melayu di daerah tersebut.Kata kunci: Asimilasi Budaya, Busana Pengantin, Aceh TamiangMalay fashion is a representation of Malay culture and culture in the field of dress, has a typical Malay symbolic value that is full of meaning and is used according to conditions, time, purpose and purpose. Cultural and religious values that characterize the Tamiang Malay bridal fashion must be maintained in the development of Malay bridal fashion. The purpose of this research is to identify the positive and negative impacts of assimilation, the development of Malay bridal fashion styles, and the existence of Malay bridal fashion in Medang Ara Village, Karang Baru District, Aceh Tamiang. The type of research is descriptive qualitative and data collection is done through observation, interviews documentation and triangulation. Data analysis techniques through data reduction, data presentation and conclusion/verification. The results showed that assimilation in Aceh Tamiang was not only caused by the multiethnic state of the community, but many factors influenced it including the attitude of community tolerance, community openness to new things, and mixed marriages with other tribes (amalgamation). Assimilation causes people to understand less about their own culture, thus changing people's views on traditional bridal attire. The bride-to-be in choosing a bridal outfit is not based on the culture she has, but based on trends and aesthetic values. The community's benchmark in choosing traditional clothes is not based on the cultural values displayed. However, some respondents still maintain the tradition and use Malay bridal clothing authentically by prioritizing cultural values. The results of this study can provide an overview of changes in Malay bridal fashion trends and the implications of cultural assimilation for the sustainability of Malay culture in the area.Keywords: Cultural Assimilation, Bridal Fashion, Aceh Tamiang