The right to self-determination is an essential international law principle that holds an erga omnes character. Also, the right is often enshrined under domestic legislation, including constitutions. The 1995 Federal Democratic Republic of Ethiopia Constitution (fdre Constitution) is one such constitution and, uniquely, it explicitly recognizes the right to self-determination including the right of secession as an unconditional right of the nations, nationalities, and peoples in Ethiopia. This paper selects the fdre Constitution and analyses whether such constitutional law frameworks better address some of the contentious matters concerning the right to self-determination under international law. In a comparative perspective (with international law), the article analyses, inter alia, how the fdre Constitution approach the questions of who the subjects of the right to self-determination are, and the substantive guarantees for exercising internal and external aspects of the right to self-determination with particular emphasis on secession as a legal right.