Combretocarpus rotundatus is a medium-sized tree that can grow up to 34 m tall. The epithet name, ‘rotundatus’ is derived from Latin word, ‘rotundus’ means rounded referring to the leaf shape. This species can be found in Sumatra, Peninsular Malaysia, Borneo and Karimon Island. In Peninsular Malaysia, it is only known from peat swamp forest at Air Hitam, Johor. It also occurs on sandy soil, freshwater swamp, and coastal forest at low altitudes (Ding Hou, 1958; Kiew et al., 2018).  

Combretocarpus rotundatus has grey-brown to brown fissured bark. Its sapwood is yellowish-brown. The leaves are alternate with petiole 0.5-1 cm long. The bole is up to diameter 58 cm with small buttresses at 1.5-2 m high. The trunk base has often shallowly fluted in swamps, producing mats of thread-like rusty brown aerial roots. The flowers are bisexual and light green to yellow in colour. Its fruits have three or four wing which is measured about 1.7-2 cm long and 1.7-2 cm wide including the wings. The seeds are narrowly spindle-shaped (Kiew et al., 2018).