The focus of this paper is an attempt to advance reasons for obeying international law with a view to ascertaining whether obeying international humanitarian law is a matter of legality or a morality. It is on this problematic premise that this paper critiqued the arguments for or/and against international law and advanced to interrogate whether or not the prominence of the emergence of international humanitarian law and its attendant substance on humanity has countered the morality question against international law generally. In order to achieve this aim, the paper uses qualitative data from the secondary sources and argues that previous studies counteracted international law on morality grounds without considering if the humanitarian law has influenced the international system in any measure in contemporary international system. It is within this gap in international law literatures that this paper seeks to interrogate, why respecting international humanitarian law, and whether the obligation is legal and a moral duty. It is thus reveal that the changing notion of sovereignty in international law is covering more spheres of law even at the domestic level, especially the human rights. And it is uncertain if the changing notion has advanced a paradigm to dismiss the naturalists’ permissive view about international law. The paper concludes that the increasing global interdependence is unavoidable and compliance with international law becomes necessary both in national and international interest. It is observable that non-compliance with a decision of the International Criminal Court does not make the international humanitarian law (international law) a moral duty or/and not law. Disobedient to court order is not peculiar only to international law. As such, international humanitarian law as an aspect of public international law has made compliance with international law a great deal of benefits to the country due to it benefits to humanity. This informs the basis of the argument in this paper. It recommends that the United Nation System should continue to strategize to promote obedience to international law among nations. Keywords: International law, Humanitarian law, Morality, Legality.