Hyposmocoma laysanensis is a species of moth of the Cosmopterigidae family. It is endemic to Laysan. The type locality is Guano Rock. The wingspan is 5.2–7.7 mm. The larval case consists of a cone-shaped structure, which is 4.5–6.0 mm in length, small and thin and decorated with bits of sand, and probably guano, woven with silk filaments. The aperture is covered with an operculum and decorated with small pebbles, or sand grains fastened by silk. The background color ranges from off-white to gray.