Over the past decades, the European Union (EU) has rapidly emerged as a maritime security actor on the international scene. Its maritime policy portfolio spans a wide range of activities, from fighting ‘blue crime’ such as piracy and human smuggling to protecting the marine environment. The EU’s capacity to secure its vital shipping routes, protect its critical maritime infrastructure, and safeguard its interests at sea are today also seen as key prerequisites of the EU’s strategic autonomy. This article breaks down the notion of maritime security actorness, asking whether and to which extent the EU is emerging as a strategic actor in this area. Empirically, it adds to the burgeoning discussion on the EU’s role in the global maritime arena. Conceptually, it seeks to advance the understanding of the EU security actorness by examining its maritime dimension and providing a versatile conceptual framework that can be applied to other contexts.