Pomacanthus sexstriatus is one of the 13 members of the genus Pomacanthus, which together with 7 additional genera make up the family of angelfishes (Pomacanthidae) in which a total of 89 species are currently described. This species is associated with coastal lagoons and reefs in waters up to 60 meters deep in the Indian and Pacific Oceans. Its distribution area covers from Sri Lanka and the Maldives archipelago to New Caledonia delimiting its southern region, while the northern limit is determined by the Ryukyu Islands of southern Japan and Micronesia.
The body Pomacanthus sexstriatus can reach up to 45 cm in total length. It has a short, slightly pointed snout with a small-sized mouth, equipped with numerous fine teeth. The operculum has a rather robust spine at its angle. The dorsal fin of the species is unique and consists of 13-14 spines and 18-23 soft rays, while the anal fin has 3 spines and 18-19 soft rays. Both the dorsal and anal fins are almost 90 degrees angulated at the rear of the body, giving the rear of the body a nearly square shape. The caudal fin is truncated.
The base coloration of adult specimens of Pomacanthus sexstriatus , both the body and the dorsal and anal fins is yellowish tan, with five well-spaced vertical black stripes across the body. The scales are surrounded by yellow, and their center is blue, producing a net effect on the body. The head is blackish and has a wide white bar running from the beginning of the dorsal to the lower edge of the operculum. The caudal fin is blackish, and both the caudal fin and the posterior parts of the dorsal and anal fins are bordered in light blue and covered with dots of the same color. Unlike adult specimens, juveniles have black head, body and fin coloration, and add to their livery approximately 15 vertical, backward-curving white stripes.