Abstract There have been different ethnic political struggles calling for self-determination through secession in Nigeria since independence. There have also been calls for ‘restructuring’ the Nigerian federation to achieve what is called ‘true federalism’ believing that it is the only panacea for each ethnic group to achieve relative independence and self-determination within Nigeria. In addition, the question of control over natural resources has been a major issue in claims for self-determination. This article examines the legal issues involved in these self-determination demands in Nigeria. It finds that self-determination started as a moral or political concept before it developed into a legal concept under international law. Under international law, self-determination has emerged as external self-determination, internal self-determination, self-determination as indigenous autonomy, self-determination as a right against intervention and economic self-determination. It has also manifested in the same form in constitutional law. Against the backdrop of these findings, it is argued that self-determination demands assume three different legal forms in Nigeria manifesting as the right to external self-determination, the right to internal self-determination and the right to economic self-determination. It is further argued that there is no right to external self-determination or secession in Nigeria. In addition, it is argued that internal self-determination manifests as the right against discrimination on ethnic grounds in Nigeria and that it constitutes a fundamental right. Lastly, it is argued that the right to economic self-determination does not exist in Nigeria as natural resources are vested in the government while the interests of the people are undermined.