The tawny-flanked prinia (Prinia subflava) is a small passerine bird belonging to the genus Prinia in the family Cisticolidae, a family of Old World warblers. It is widespread and common in most parts of Africa south of the Sahara.
It is 10-13 centimetres in length with a long, narrow, graduated tail and a fairly long, slender bill. The tail is often held erect or waved from side to side. The upperparts are grey-brown with rufous-brown edges to the flight feathers and a rufous tinge to the rump. The throat and breast are whitish while the flanks and vent are warm buff. There is a whitish stripe over the eye and the lores are dark. The tail feathers have a white tip and a dark subterminal band. The sexes are similar in appearance. Non-breeding birds have a longer tail than breeding birds. Juveniles have pale yellow underparts and a yellowish bill. There are many recognised subspecies. The call is short, wheezy and rapidly repeated. The song is a monotonous series of shrill notes. The male often sings from an exposed perch. The pale prinia (P. somalica) of North-east Africa is similar but paler and greyer with whitish flanks. It inhabits drier, more open habitats than the tawny-flanked prinia. The river prinia (P. fluviatilis) of West Africa is also paler and greyer and has a longer tail. It is restricted to waterside vegetation.