Shell large (to 225 mm: Hutsell et al., 1997), oblong, lightweight, little arched, little convex. Spire low to somewhat elevated, visible in ventral view. Holes medium sized to large, oblong, elevated, usually 3-4 open. Dorsal surface uneven, with broad and low cords, regular growth lines. Columella narrow. Carina between row of holes and columella little distinct. Coloration in colabral bands of various colors: Sepia, cyan, rust, white. Nacre often milky blue. No muscle scar.

Haliotis discus hannai has a strongly undulating dorsal surface. Haliotis k. kamtschatkana from the northeastern Pacific has a higher shell, and regular low and broad spiral cords without the fine spiral threads. Haliotis diversicolor from southern Japan and the Indo-Malayan Archipelago lacks the undulating dorsal surface, has a sturdier shell, a less elevated spire, and the dorsal surface slopes smoothly in the area between the row of holes and the columella. The Japanese H. gigantea is rounder, has a smoother dorsal surface and is usually overall orange in color.

Japan: Honshu, Kyushu, Shikoku