This chapter considers that political philosophers in recent years are paying growing attention to the legitimacy of international law and international institutions and are asking who has the right to rule and adequate standing to create international laws, and how. It attempts to contribute to this debate in normative political philosophy through the more specific lens of democratic legitimacy. After presenting certain conceptual clarifications, the chapter identifies three basic principles of democratic legitimacy: the principle of ultimate popular control, the principle of democratic equality, and the principle of deliberative contestability, which can be instantiated in six more concrete requirements. The chapter continues by exploring the limitations of two influential views on the democratic legitimacy of international law. Finally, the chapter concludes by expressing some scepticism about the degree to which the current system of sources of international law is democratically legitimate.