Perennial herb, 10-40 cm. Stem below the leaves or nearly equal, densely open. Show yellow pubescent. Leaves three, leaflets with a short handle, thick texture, obovate or rhombic, dilute a few round, 3-7 cm long, 2-6 cm wide, top obtuse, base broadly cuneate, lateral leaflets base oblique, margin notched serrate, serrated acute, dark green above, almost no hair, pale green beneath, sparsely hairy, denser along veins; petiole 2-10 cm long, densely pubescent carry yellow. Cymes, flowers 5-15 flowers, inflorescence a short handle under the mask of leaflets; flowers bisexual, 1.5-2 cm in diameter; sepals ovate, slightly longer than the sepals deputy vice sepals oval lanceolate, entire, rare deeply 2-lobed, fruit when expanded; petals white, nearly round or oval obovoid, base with no significant claw; stamens 20, unequal; pistil very much.