Hartert's Leaf-warbler breeds in southern China and winters in places including Hong Kong. It searches tree trunks for food.
The Hong Kong account describes a pale crown stripe between dark lateral crown stripes, with a supercilium that is yellow in front and white behind. Yellow on the underparts varies among subspecies.
In Hong Kong during winter it uses closed-canopy forest and shrubland, joining mixed-species flocks in the canopy and high understory. The account also describes nuthatch-like searching along tree trunks.
An extinction-risk assessment has not been added yet.