[3] Leucoagaricus laosensis is a small dapperling mushroom with a brown scaly cap and thin (up to 3mm wide) white flesh.

As it matures, the cap expands to become flat or plano-convex with only a slight, low umbo.

The margins are straight, with sulcate striations, and may be appendiculate with white and light brown veil remnants.

Gills: Free, crowded, and white, with an eroded edge and a ventricose bulge, measuring 4–6 mm wide.

[3] The specific epithet laosensis is named in reference to the location in which this species was found, Laos.