Andeimalva peruviana Dorr & Romero-Hernández, sp. nov., the third Peruvian endemic in a small genus of five species, is described and illustrated from a single collection made at high elevation on the eastern slopes of the Andes. Molecular phylogenetic analyses of nuclear ribosomal ITS sequence data resolve a group of northern species of Andeimalva found in Bolivia and Peru from the morphologically very different southern A. chilensis. The new species bears the largest flowers of any Andeimalva and is compared with Bolivian A. mandonii. A revised key to the genus is presented.