Annual twining vine, or nearly erect, sometimes the top winding shape. Stem near glabrous. Pinnately compound leaves with 3 leaflets; stipules lanceolate, ca. 1 cm, with students at a short distance extension, cable lines; leaflets ovate rhombic, 5-15 cm long, 4-6 cm wide, apex acute, margin entire or subentire, sometimes pale purple, glabrous.

Axillary racemes, with long stalks; flowers 2-6 poly was born at the top of the inflorescence, often fleshy pedicel densely glandular; calyx campanulate, pale green, 6-10 mm long, teeth lanceolate; corolla yellow tinged with purple, ca. 2 cm, with the valve flap handle, upper petal oblate, width of 2 cm, emarginate, base slightly winged ears, slightly triangular, slightly curved keel; ovary linear, hairy.

The pod drooping, erect or oblique, linear, 7.5-70 (90 cm) long, 6-10 mm wide, slightly fleshy expansion or solid, a plurality of seeds; seed oblong or cylindrical or slightly kidney shaped, 6-12 mm long, yellowish white, dark red or other colors. Flowering period 5-8 months