Heniochus singularius, the singular bannerfish, is a species of marine ray-finned fish, a butterflyfish from the family Chaetodontidae.

[2] Heniochus singularius has a wide Indo-Pacific distribution which extends from the central Indian Ocean around the Maldives and the Chagos Islands east to Samoa.

The range extends north to southern Japan and south to northern Australia.

[1] In Australia it is found from Shark Bay to the Dampier Archipelago and the offshore reefs of Western Australia, and along the northern Great Barrier Reef south as far as Moreton Bay in Queensland; it also occurs at Christmas Island.

[4] Heniochus singularius was first formally described in 1911 by the American zoologists Hugh McCormick Smith and Lewis Radcliffe with the type locality given as Alibijaban in Ragay Gulf of Luzon in the Philippines.