Given the centrality of law in the creation, decision-making, and impact of the United Nations Security Council, the deliberative discourses among Security Council Members, and the necessity for China to articulate its reasons publicly for its actions within the Security Council, the roles that China plays within the Security Council illuminate and clarify its approaches to the current international legal order. This article explains how law serves as a constitutional–normative framework within which the Security Council must function, followed by a discussion of how the Security Council in turn may serve as a locus of deliberative discourses that delineate, influence, and constrain its members’ state behaviours. It challenges the view that law plays a limited role on matters of international security by exploring China's voting behaviour in the Security Council and the arguments that it has proffered. It also discusses how China may respond to a draft Security Council resolution aimed at its conduct other than simply by vetoing it, and how it has taken a proactive role in the maintenance of international peace and security through the Security Council.