Ilanga laevissima is a species of sea snail, a marine gastropod mollusk in the family Solariellidae.

It is ornamented with waved zigzag and acutely angular light and dark brown streaks.

The 5½ whorls are slightly convex, moderately sloping, separated by simple, deep-channeled sutures.

The columellar margin is straightened, forming an obtuse angle where it joins the basal lip.

[3][4] This marine species occurs off Zululand to the Atlantic Cape Province, South Africa