I describe a new species of Oreophryne from Woodlark Island, the most isolated large island in southeastern Papua New Guinea. The new species is a member of the O. equus species group, characterized by having a “whinny” call consisting of a rapid series of high-pitched peeps. It differs from other members of that group in a combination of features, including having a cartilaginous connection between the scapula and procoracoid, well-webbed digits on the feet, fifth toe longer than the third, a largely unicolor brown dorsum, and red flash markings on the hidden surfaces of the thighs. All members of this species group inhabit the southeasternmost portion of Papua New Guinea, with most species endemic to single offshore islands. The species is common in secondary rain forests on Woodlark, but continued commercial interest in developing large-scale extractive industries on the island could potentially threaten this and other endemic species on Woodlark if developments were to occur across a large-enough area of the island.