The black-chested prinia (Prinia flavicans) is a species of bird in the family Cisticolidae.

It is found in Angola, Botswana, Lesotho, Namibia, South Africa, Zambia, and Zimbabwe.

Its natural habitat is dry savanna.

Prinias are small warblers that can be distinguished from other warblers by their long tails often held in a near-vertical position. All species are sexually monomorphic. There are four species in the Prinia genus in southern Africa. The three other species are as follows: tawny-flanked prinia (Prinia subflava), Karoo prinia (Prinia maculosa), and Drakensberg prinia (Prinia hypoxantha).

Of these four, the black-chested prinia is the only species that has different breeding and non-breeding plumages. The black-chested prinia is aptly named for the charcoal-colored breast band apparent in its breeding plumage.

Black-chested prinias are small, long-tailed warblers whose body sizes range from 13 to 15 centimeters. They are a pale golden-brown on their dorsal side and during the non-breeding season they have pale yellow dorsal plumage. In their alternate plumage (breeding season), they develop a black breast-band and their underparts become white or a buttery yellow.

Black-chested prinias make a loud, repeated "chip-chip-chip" call as well as a buzzy sequence of "zrrrt-zrrrt-zrrrt" sounds.