This article examines levels and patterns of legitimacy beliefs toward one of today’s most developed global multistakeholder regimes, the Internet Corporation for Assigned Names and Numbers (ICANN). Two complementary surveys find that levels of legitimacy perceptions toward ICANN often rank alongside, and sometimes ahead of, those for other sites of global governance, both multilateral and multistakeholder. Moreover, average legitimacy beliefs toward ICANN hold consistently across stakeholder sectors, geographical regions, and social groups. However, legitimacy beliefs decline as one moves away from the core of the regime, and many elites remain unaware of ICANN. Furthermore, many participants in Internet governance express only moderate (and sometimes low) confidence in ICANN. To this extent, the regime’s legitimacy is more fragile. Extrapolation from mixed evidence around ICANN suggests that, while multistakeholder global governance is not under existential threat, its legitimacy remains somewhat tenuous.