Fifteen species of amphibians are reported from the Machalilla National Park, located in coastal western Ecuador. Scinax quinquefasciatus, Trachycephalus venulosus, and Leptodactylus ventrimaculatus are reported from the area for the first time. Several amphibian species are rangerestricted and endemic. The amphibian fauna of this national park is related to the Tumbesian endemic region. Updated information is presented for Ceratophrys stolzmanni and Leptodactylus ventrimaculatus.