Ilex rotunda, the Kurogane holly or round leaf holly, is a smooth evergreen tree from the holly genus, reaching 18 m at maturity (although 20 m is also reported). It has spineless leaves and clusters of bright-red berries.
The tree blossoms in April and the seeds become ripe from October to December. The flowers are dioecious. The fruits contain flavonols. In Japan, kurogane holly is one of the hibakujumoku trees. It is also the official tree of several Japanese municipalities.