ABSTRACT This study concerns the millipede genus Leptherpum Attems, 1931, which contains nine valid species distributed across the Amazonian rainforest of northeastern South America. The type species L. carinovatum (Attems, 1898) is reexamined based on the type material and high-resolution photographs, including the first scanning electron micrographs of this species. The following three new species are described: Leptherpum tialaura sp. nov. from the state of Pará, Brazil; Leptherpum battirolai sp. nov. from the state of Amazonas, Brazil; and Leptherpum buenovillegasi sp. nov. from the commune of Maripasoula, French Guiana. A brief review of Leptherpum taxonomy and geographic distribution is provided, along with a key to males.