Annual herb with round, oval or spindle-shaped tuberous roots in the underground part. The shape, skin color and flesh color of tuberous roots vary with varieties or soils. Stems procumbent or ascending, occasionally twining, multi-branched, cylindrical or angular, green or purple, sparsely pilose or hairless, and stems are prone to adventitious roots. The shape and color of leaves often vary from variety to variety, and sometimes they have different leaf shapes on the same plant. Usually, they are broadly oval, 4-13cm long and 3-13cm wide, and the leaves are completely or 3-5(-7)-lobed. The lobes are broadly ovoid, triangular ovoid or linear-lanceolate, and the base of the leaves is heart-shaped or nearly truncated. Petioles vary in length, 2.5-20 cm long, and are sparsely or glabrous. Cymes are axillary, with 1-3-7 flowers gathered in an umbrella shape, and the peduncle is 2- 10.5 cm long, slightly stout, hairless or sometimes puberulent; Bracts small, lanceolate, 2-4 mm long, apical awn or acute, caducous; Pedicel length 2- 10 mm; Sepals are oblong or oval, unequal in length, the outer sepals are 7- 10 mm long, the inner sepals are 8- 1 1 mm long, and the top suddenly becomes an awn tip, with no hair or sparse cilia; Corolla pink, white, lavender or purple, bell-shaped or funnel-shaped, 3-4 cm long, glabrous outside; Stamens and styles are embedded, and filaments are hairy at the base; Ovary 2-4-loculed, hairy or sometimes glabrous. Flowering habits vary with varieties and growth conditions. Some varieties are easy to bloom, others will bloom in dry climate, and they are common in areas with high temperature and short sunshine, but rarely in areas with low temperature. Capsule ovoid or oblate, with false diaphragm and divided into 4 cells. Seeds 1-4, usually 2, glabrous. Because sweet potato is cross-pollinated, self-pollination is often not fruitful, so sometimes it only blooms but does not bear fruit.