Hawaiian hanging is not very long, the maximum body length is 25cm, the adult is oval and laterally flat, and the tail shank has a sharp and pointed forward sagittal spine. The head is small and the profile of the back of the head is not particularly prominent. The mouth is small, the end position, the snout is papillary, the upper and lower jaws have bristle-like slender teeth, the teeth are movable, and the teeth are enlarged and flattened. The spines of the dorsal and anal fins are sharp; the pectoral fins are nearly triangular; the caudal fins are concave. Body covered with fine comb scales, with dense small scales along the base of the dorsal and anal fins. The adult fish has a blue body, with brown stripes all over the body, and a pink-blue and black circle pattern on the snout. The fins of the body are the same color as the body, with brown stripes, and black tail spines on the caudal peduncle.

Like all Ctenodon species, the hawaiian halibut's young Fish and adult fish are very different. Juveniles are orange-yellow with mottled brown stripes on the sides, yellow-brown dorsal and anal fins with black stripes, soft rays with blue spots at the end, and white caudal fin. As it grows, the body gradually turns orange-red, and the body stripes, dorsal, anal and caudal fins also gradually appear purple. When it grows to about 7cm, the purple color of the body gradually fades, replaced by the appearance of dark green, and the lines on the body begin to be dense and extend laterally.