[3] Acer japonicum is a small deciduous tree growing to 5–10 m (rarely 15 m) tall, with a trunk up to 40 cm in diameter.

The flowers are 1 cm in diameter, dark purplish-red with five sepals and petals; they are produced 10–15 together in drooping corymbs in early spring as the leaves start to open.

[4] Its preferred growing conditions are similar to those of Acer palmatum, but it is sometimes considered more tolerant of cold, especially compared to the more delicate cultivars of the latter.

[6] Other popular cultivars are 'Aconitifolium'[7] ("downy Japanese maple") which has deeply incised leaves; and 'Green Cascade', with drooping to pendulous branches.

Another related species, Acer sieboldianum (Japanese: コハウチワカエデ kohauchiwakaede), is best distinguished by its yellow (not red) flowers, and smooth bark even on old trees.