Zelkova serrata (Keaki or Japanese Zelkova) is a species of Zelkova, native to Japan, Korea, eastern China, and Taiwan.

It is a medium-sized to large deciduous tree growing to 20-35 m tall, with a trunk up to 2 m diameter. The leaves are alternate, 5-11 cm long and 2-5 cm broad, with a sharply serrated margin. The flowers are inconspicuous and greenish, with no petals, and are wind-pollinated. The fruit is a small nutlet 3 mm diameter.

It is often grown as an ornamental tree. Keaki wood is valued in Japan. The tree is a symbol of Saitama Prefecture. The name Keaki derives from the Japanese name of the species, .

Rosales | ケヤキ | Zelkova serrata