The yellow-bellied elaenia (Elaenia flavogaster) is a small bird of the tyrant flycatcher family. It breeds from southern Mexico and the Yucatán Peninsula through Central and South America as far as northern Argentina, and on Trinidad and Tobago.
Adults are 16.5 cm long and weigh 24 g. They have olive-brown upperparts, a white eye ring, a bushy divided crest and a white crown patch in the parting. The throat is pale and the breast greyish, with pale yellow lower underparts. The call is a nasal breeer, and the song is a wheezing zhu-zhee-zhu-zhee.