The beetle fauna of Peru has not been enumerated since Blackwelder (1944–1957). This contribution is the first modern synopsis of beetle families, based on ongoing fieldwork and a literature review. Ninety nine families of beetles are now documented from Peru and nine families are reported in Peru for the first time—Biphyllidae, Bothrideridae, Eucinetidae, Monotomidae, Rhipiceridae, Scirtidae, Scraptiidae, Silvanidae, and Throscidae. A species list for each family, updated higher taxonomy, and relevant literature citations are presented. Most families are so poorly known in the tropics and so poorly represented in museum collections, that their rarity and/or conservation status cannot be determined. Altogether the project represents the first modern catalogue of the entire beetle fauna of a hyperdiverse Neotropical country.