This species inhabits rocky inshore reefs exposed to wave action and currents to depths of 3m - 15m, and is most frequently observed near large boulders in the shallow subtidal zone. Bumphead damselfish is a highly aggressive. Adults are dusky dark grey brown, median fins with slight golden-brown hue; juveniles are mainly bright blue on upper half of head and body, and yellow on lower half. It is mainly herbivorous, feeding on algae.