The olive-bellied sunbird (Cinnyris chloropygius) is a species of bird in the family Nectariniidae.

It differs from the slightly smaller tiny sunbird in having a larger beak and no blue bars among the red breast plumage.

It forages in the lower parts of the canopy, feeding on caterpillars, beetles, spiders, nectar, flowers and seeds.

The nest is a straggly affair formed from grasses, strips of bark and leaves, and lined with fine material.

[2] The olive-bellied sunbird is a common species with a very wide range, and the population trend is thought to be steady.