The Fourspot butterflyfish, Chaetodon quadrimaculatus, is a butterflyfish of the family Chaetodontidae found in the Pacific Ocean from the Ryukyus, Ogasawara (Bonin) Islands and Taiwan to the Hawaiian, Marquesan, and Pitcairn islands, south to the Samoan and Austral Islands and the Marianas and Marshall Islands in Micronesia, at depths down to 49.21 ft (15 m). Its length is up to 6.30 in (16 cm).
The Fourspot butterflyfish is found almost exclusively on exposed seaward reefs, and feeds mainly on polyps of Pocillopora. It is either solitary or found in pairs.
Reproduction is oviparous, with pairs forming during breeding.