The queen angelfish (Holacanthus ciliaris), also known as the blue angelfish, golden angelfish, or yellow angelfish, is a species of marine angelfish found in the western Atlantic Ocean. It is a benthic (ocean floor) warm-water species that lives in coral reefs. It is recognized by its blue and yellow coloration and a distinctive spot or “crown” on its forehead. This crown distinguishes it from the closely related and similar-looking Bermuda blue angelfish (Holacanthus bermudensis), with which it overlaps in range and can interbreed.

Adult queen angelfish are selective feeders and primarily eat sponges. Their social structure consists of harems which include one male and up to four females. They live within a territory where the females forage separately and are tended to by the male. Breeding in the species occurs near a full moon. The transparent eggs float in the water until they hatch. Juveniles of the species have different coloration than adults and act as cleaner fish.

The queen angelfish is popular in the aquarium trade and has been a particularly common exported species from Brazil. In 2010, the queen angelfish was assessed as least concern by the International Union for Conservation of Nature as the wild population appeared to be stable.