Euonymus castaneifolius is a tree in the family Celastraceae. The specific epithet ' is from the Latin meaning 'chestnut-coloured leaves'.
Euonymus castaneifolius grows up to tall with a trunk diameter of up to . The smooth bark is grey-brown. The flowers are white. The fruits ripen red and measure up to long.
Euonymus castaneifolius grows naturally in Sumatra and Borneo. Its habitat is lowland mixed dipterocarp to montane forests from sea-level to altitude.