Predators include reef sharks, tunas, snappers, jacks, groupers, and barracudas. Juveniles may also be taken by trumpetfish. Pelagic eggs are commonly eaten by small bar jacks, yellowtail snappers, and the black durgon.
Because of their flattened shape and sharp caudal spines, it is difficult for predators to swallow blue tangs.
Defense from predators while grazing and spawning is also accomplished by schooling. Attacks are more often observed on solitary fish.