The leaves of Crotalaria humilis are trifoliolate, meaning that every leaf is divided into three leaflets. The petiole (leaf stalk) is long and straight, but there are no petiolules (leaflet stalks). Tiny, spear-shaped to cone-shaped stipules are present at the petiole base.

Leaflet shape is obovate to oblong, tapering to the base and rounded at the tip that is sometimes notched or hair-tipped. The margins are entire. The blade halves fold in along the midrib, the leaflets becoming about 1,5 cm long. Blades are dull to fresh green, sometimes slightly blue-green and faintly hairy on the lower surfaces, the hairs pressed flat (Le Roux, et al, 2005; iNaturalist).