Austrochaperina blumi is a species of frog in the family Microhylidae. It is endemic to New Guinea and known from the northern slopes of the New Guinean Central Range in Western New Guinea (Indonesia), and from the Bewani, Torricelli, and Hunstein Mountains in Papua New Guinea. The specific name blumi honors J. Paul Blum, the herpetologist who collected the type series. Common name Kosarek land frog has been proposed for it.