Margarella pruinosa is a species of sea snail, a marine gastropod mollusk in the family Calliostomatidae.

It is ornamented with irregular oblique striae and decussated with evanescent lines, only visible under a lens.

The oblique, shining aperture is lunate, transversely oblong, and obscurely lirate inside.

Its, margins are subparallel, the outer subsinuous, the basal arcuate, the columellar incurved.

The twisted columella is incurved, a little thick, callous, forming an obtuse angle at the base, and emitting a thick, white, shining, slightly dilated callous closing the umbilicus, and bipartite by a longitudinal sulcus.