The Peruvian tyrannulet (Zimmerius viridiflavus) is a species of bird in the family Tyrannidae. As traditionally defined, it is endemic to Peru, but recent genetic evidence suggests it should include the taxon flavidifrons as a subspecies, in which case the range of the Peruvian tyrannulet extends into far southern Ecuador. Alternatively, flavidifrons is sometimes considered a separate species, the Loja tyrannulet, but it is not closely related to the golden-faced tyrannulet as previously believed. The natural habitat of the Peruvian tyrannulet is subtropical or tropical moist montane forests.