Olivancillaria is a genus of sea snails, marine gastropod mollusks in the subfamily Olivancillariinae of the family Olividae.
The mantle shows a large, thick, fleshy appendage behind.
The operculum is distinct, half-ovate with an subapical nucleus.
The spire is short with the suture not canaliculated to the apex.
The columella shows two or three oblique plaits anteriorly, and has a large callosity posteriorly.