Eucommia ulmoides is a deciduous tree with a height of 20 meters. Branchlets smooth, yellowish brown or pale, with flaky pith. Bark, branches and leaves all contain gum. Simple leaves alternate; Oval or ovoid, 7 ~ 15cm long and 3.5 ~ 6.5cm wide, tapering at the top, wide wedge-shaped at the base, serrated at the edge, with sparse hairs on the young leaves and dense hairs on the lower ones, smooth on the old leaves and sparse hairs on the lower veins; Petiole length 1 ~ 2 cm. Flowers are unisexual, dioecious, open at the same time as leaves, or open the first leaf, born in the axils of bracts at the base of annual branches, with pedicels; No perianth; The male flower has 6 ~ 10 stamens; The ovary of the female flower is bare and elongated, with 1 cell and a forked style at the top. Samara is oval, flat, concave at the top and contains 1 seed. The flowering period is from April to May. The fruiting period is September.