Abrus laevigatus is a shrub, with slender, wide-climbing, woody branches, sparsely covered in yellow hairs, up to 6 m long. Leaves are pinnate and alternate. Leaflets are 6-10-paired, opposite. Leaflet stalks are short, blades oblong or obovate-oblong, 5–30 × 3–10 mm, membranous, sparsely white bristly or densely white hairy below, hairless or hairy above, rounded or heart-shaped at base, flat and with mucro at the tip. Flowers are in dense, several-flowered racemes, borne in leaf axils, 30–100 mm long. Flowers are 3-9 mm long. Sepal cup is bell-shaped, 4-toothed, white-bristly or densely grey-hairy. Flowers are white, lilac or mauve. Seed pods are oblong, 50–65 × 8–15 mm, densely white-hairy, splitting open, with 4–12 seeds. Seeds are black to brown or black, lustrous to slightly lustrous, elliptic or ovoid, compressed. Flowering time is in summer, from September to May.

In South Africa, it may be confused with Abrus precatorius, known as luckybean creeper or jecquirty bean, its flowering branches are often bare where those of A. laevigatus are leafy. They are easily told apart when in fruit, the pods of A. laevigatus are longer and narrower and a single pod, whereas those of A. precatorius are in clusters.