The Mountain Leaf Warbler is a small bird that searches among leaves for insects in Borneo's montane forests. Pale lines bordering its dark crown are a useful field mark.
Pale stripes border the dark crown, and the upperparts are greenish. The field guide gives a body length of about 10–11 cm.
In Bornean montane forest it joins mixed-species flocks, moving from the mid-storey to the canopy and gleaning insects from leaves.
An extinction-risk assessment has not been added yet.