Neptunia lutea, commonly called the yellow-puff,[1] is an herbaceous plant in the legume family (Fabaceae).

It is native to the United States, where it is primarily found in the South Central region, extending eastward into the Blackland Prairies of Alabama and Mississippi.

Its stems are covered with soft spines, but is not nearly as prickly as the similar-looking Mimosa nuttallii.

The sprawling stems of this plant branch frequently, with each branch growing as long as 5 ft. Leaves are alternate and stalked, bipinnate, looking much like tiny fern fronds.

Each individual flower has five minute petals and ten stamens.