Trees or large shrubs, evergreen. Branchlets never spinose, never corky or winged. Stipules 2, free, caducous, leaving a short transverse scar on each side of leaf base. Leaves alternate in several ranks; leaf blade ovate to narrowly lanceolate, margin denticulate; usually 3(-5)-veined from base (venation pinnate in T. levigata); secondary veins anastomosing before reaching margin. Inflorescences subsessile. Flowers unisexual or polygamous, shortly pedicellate. Male flowers: (4 or)5-lobed; tepals incurved, valvate, or ± imbricate. Stamens equal in number to tepals. Ovary rudimentary, basally with perigynous pubescence. Female flowers: (4 or)5-lobed. Ovary sessile, basally with perigynous pubescence. Drupes 1.5-5 mm in diam., erect, elliptic to ± globose; tepals and stigmas persistent or rarely perianth caducous; exocarp ± fleshy, endocarp bony. Endosperm fleshy; embryo curved or involute; cotyledons narrow.

Trema species are often found in E and SW China, particularly in disturbed and degraded habitats.

About 15 species: tropical and subtropical areas; six species (two endemic) in China.