A new species of frog of the genus Pristimantis is described from a montane forest between 1700 and 1800 m a.s.l. of the Pui Pui Protected Forest (Región Junín) in central Peru. Pristimantisashaninkasp. n. is described based on five adult females (snout–vent length 23.1–26.7 mm) and ten juveniles (snout-vent length 10.6–13.4). It differs from its congeners by having the skin on dorsum shagreen with many conical tubercles giving it a spinose appearance, lacking a tympanum, having groin, anterior and posterior surfaces of thighs uniformly grayish brown, and a pale bronze iris with fine black reticulations, a median reddish hint horizontally across iris, and a black narrow vertical streak from pupil across lower and upper half of iris. Among the Peruvian Pristimantis that lack a tympanum, P.ashaninkasp. n. is morphologically most similar to P.lirellus, P.martiae, and P.rhabdocnemus. However, 16S DNA barcoding revealed clear distinctions between all four species of Pristimantis.