The Olive Sunbird is olive above and yellowish-green below. It favors forest cover and eats nectar, insects, and spiders. Yellow pectoral tufts occur in all males and in females from some populations.
The back is olive, and the face is darker than the crown and back. The breast and belly are yellowish-green. Males have yellow pectoral tufts, and females have them in some populations.
It often stays under cover and is usually alone, though loose groups may form at rich feeding sites. It eats nectar, insects, and spiders.
An extinction-risk assessment has not been added yet.