The Malam Balacuik Marapulai tradition is a customary wedding ritual that has been preserved and practiced for generations by the people of Marunggi Village, South Pariaman District, Pariaman City, West Sumatra. Conducted on the evening prior to the marriage contract (akad nikah), this tradition serves as a medium for moral guidance, mental preparation, and the reinforcement of responsibility for the prospective groom (marapulai). This study aims to examine the implementation of the tradition, explore its philosophical values, and analyze its position from the perspective of 'urf (customary practice) in Islamic law. This research employs a qualitative field research approach. Data were collected through interviews,observations,and documentation involving traditional leaders (niniak mamak), customary authorities, participants, and members of the local community. The findings reveal that the implementation of the tradition consists of several stages, including the delivery of customary speeches (sasambahan), the placement of ceremonial cloths, the melimaukan ritual, the symbolic striking of the groom using a palacuik, the provision of customary advice, and a communal meal. The tradition embodies significant values, including responsibility, moral education, respect for customary authority, social. solidarity, and spiritual preparedness. From the perspective of 'urf, the Malam Balacuik Marapulai tradition can be classified as 'urf şahīh (valid custom) because it is widely accepted by the community, continuously practiced, beneficial to society, and not contradictory to the fundamental principles of Islamic law. Nevertheless, the practice of unrestricted interaction between men and women during the ceremony requires adjustment to ensure greater conformity with Islamic ethical and legal values.