Oreobates ayacucho is a species of frogs in the family Craugastoridae. It is endemic to Peru and known from a few localities in the Ayacucho Region in the Peruvian Andes. The species is only known from 11 specimens.
The female holotype measures 29 mm (1.1 in) in snout–vent length (SVL). Two adult males measure 19 and 25 mm (0.75 and 0.98 in) SVL. The snout is short and rounded. The tympanic membrane is absent but the tympanic annulus is visible beneath skin, partly covered by supratympanic. Skin on the dorsum is smooth and has small, elongate tubercles, and forms discontinuous occipital and dorsolateral folds. Fingers and toes have knob-shaped terminal phalanges but no webbing. The dorsum and venter are dark brown, with the folds and some warts almost black. The iris is almost black and has some golden reticulation.
The male advertisement call consists of a group of 3–5 pulsed, amplitude-modulated notes. The call lasts less than a second, but is repeated at a rate of 2.5–2.9 calls per minute when males are motivated.
