The Ecuadorian territory is divided into four natural regions: the coastal lowlands, the Andean highlands, the Amazon basin, and the Galapagos Islands. Each of these regions has its own ecosystems and specific vegetation. The purpose of this work is to compile an updated catalog of the Scarabaeinae (Coleoptera: Scarabaeidae) of Ecuador that includes distributional data and several nomenclatural acts. We compiled data from 25 scientific collections, with the examination of 13,550 scarabaeines; additionally, 390 bibliographic references were reviewed for their taxonomic histories. The Scarabaeinae fauna from Ecuador is represented by 33 genera and 223 species, with 45 range-restricted species; 27 species were erroneously recorded from the country. The following nomenclatural acts are made: (A) two new status as valid species: Canthon (Glaphyrocanthon) ohausi Balthasar, 1939, stat. n., and Deltochilum (Calhyboma) arrowi Paulian, 1939 stat. n.; (B) one new synonym: Uroxys magnus Balthasar, 1940 = Uroxys latesulcatus Bates, 1891, syn. n.; (C) two revalidated names: Canthidium (Canthidium) orbiculatum (Lucas, 1857) and Dichotomius (Luederwaldtinia) fortepunctatus (Luederwaldt, 1923); and (D) ten lectotypes designated for: Choeridium orbiculatum Lucas, 1857; Choeridium cupreum Blanchard, 1846; Canthidium coerulescens Balthasar, 1939; Canthon angustatus Harold, 1867; Canthon angustatus ohausi Balthasar, 1939; Deltochilum tessellatum Bates, 1870; Pinotus fortepunctatus Luederwaldt, 1923; Pinotus globulus Felsche, 1901; Uroxys latesulcatus Bates, 1891; and Uroxys magnus Balthasar, 1940. The type specimens related to the new nomenclatural acts are illustrated and the maps of the geographical distribution of all species are provided.