The legal adoption and the customary adoption are usually presented in terms of the differences between them. However, this article aims at highlighting the similarities between the civil law and the aboriginal values in terms of adoption, and develops a hypothesis concerning the emergence of an interface between the two cultures. The analysis is based on the judiciary decisions published in the last ten years and on the report written by the working group on the adoption regime in the province of Quebec. In the first part, the author deals with the importance of cultural relativism in the apprehension of customary adoption. The second part is dedicated to the admission of the customary adoption by the Quebec courts. The author explores the difficulties related to the coexistence of the statutory law and the customary law. She also illustrates how complex is the interpretation regarding the interest of the aboriginal child, given the importance of the individual and collectives rights. Finally, the third part of the study focuses on the reform of the adoption in the province of Quebec and on the recognition of the customary adoption. The author presents the new parameters proposed for the support of a possible reform of the legal adoption along with the issues around the recognition of the customary adoption. The realities are not necessarily the same in both cultures, but in both cases, the challenge consists in preserving the rights and the interests of the child whom is subject to adoption, regardless of the form it takes.