Anatoma tangaroa is a species of small sea snail, a marine gastropod mollusc or micromollusc in the family Anatomidae.
The width of the shell attains 1.79 mm, its height 1.42 mm.
This marine species is endemic to New Zealand and occurs off the Middlesex and King Banks, Three Kings Islands, west of Cape Reinga and on the Kermadec Ridge.