Naso maculatus was first formally described in 1981 by the American ichthyologists John Ernest Randall and Paul J. Struhsaker with its type locality given as the northern shore off Haliewa on Oahu in Hawaii.

[3] Naso maculatus is a slender bodied unicornfish which has no protuberance growing from the head at any size.

There are two small bony plates on the caudal peduncle each with a roughly semi-circular keel which projects outwards.

[1] In Australia it has been recorded from the Capricorn Group off southern Queensland, Lord Howe Island and Middleton Reef.

[5] This species is found in deep water at depths between 20 and 220 m (66 and 722 ft)[1] on the seaward slopes of reefs.