Megastomia simplex, common name the simple pyramid shell, is a species of sea snail, a marine gastropod mollusk in the family Pyramidellidae, the pyrams and their allies.

[1][2] The white, rather solid shell has a smooth appearance.

The length of the shell measures 4 millimetres (0.16 in).

[3] The type specimen of this marine species was found off Port Jackson, New South Wales, Australia.

This Pyramidellidae-related article is a stub.