Caulophyllum thalictroides, the blue cohosh, is a species of flowering plant in the Berberidaceae (barberry) family.

[citation needed] The Greek-derived genus name Caulophyllum signifies "stem-leaf", while the specific name thalictroides references the similarity between the large highly divided, multiple-compound leaves of meadow-rues (Thalictrum spp.)

From the single stalk rising from the ground, there springs a single, large, three-branched leaf, giving rise to a yellow-flowered inflorescence, followed by bluish berries, coated with a glaucous, waxy bloom, somewhat similar in appearance to sloes.

The plant is found in hardwood forests and favors moist coves and hillsides, generally in shady locations, in rich soil.

The plant is pollinated early in the season by certain bee species, which are attracted by the nectar glands present on the petals.