Iniistius trivittatus is a species of wrasse currently only known from the Pacific waters off Hong Kong and Taiwan. This species inhabits reefs from the surface to 10 m (33 ft) deep. It can reach 30 cm (12 in) in total length.

It is deep bodied and extremely laterally compressed as in all members of its genus. It is distinctively coloured, generally pale yellow with three broad, dark, vertical bars on its body. A further diagnostic trait is the presence of a deep notch between the first two spines of the dorsal fin.