While the concept of normative positivism expresses the thesis that legal positivism should be entrenched in legal systems and the participants of those legal systems should regard law as analyzed by legal positivism, it also encapsulates a group of criticisms directed to legal positivism. In this paper, it will be argued that the criticism directed at legal positivism in the way that it is a normative theory, regardless of all appearances, could be right in terms of determining and describing the boundaries of the social fact in question, though not in terms of the descriptiveness of legal positivism per se. The aspect of this approach that cannot be met by the previous counter-arguments is that it concedes that legal positivism’s analysis is a descriptive one and instead focuses on the scope of that analysis. In this paper, H.L.A. Hart’s ideas on international law will be examined in the context of this approach. We argue that, though Hart’s analysis of municipal law could be taken as successful, he is wrong that his analysis presents a general and exclusive analysis of the concept of law. In this sense, it will be argued that the fact that Hart excludes international law from his analysis without a valid justification implies a normative attitude.