Biogeographical provinces have been defined for the earthworm fauna of continental Portugal by subjecting data obtained at 100 sites distributed among 23 zones to correspondence analysis and dendritic clustering so as to detect faunistically similar groups of zones. Various measures of species importance and interspecific association were calculated in order to characterize the provinces so detected. On the basis of our findings and the existing literature, ve propose that Galicia and Northern Portugal be included in a Galaico‐Lusitanian Province characterized by the joint dominance ofA. caliginosaand the three typical speciesD. madeirensis, D. taedraandA. olivtirae, which are accompanied by other, more widely distributed species; and that continental Portugal south of he River Mondego be considered an Atlantic Province character‐zed by the dominance ofA. caliginosa, A. roseaand the≪A. molleri≫:omplex species, and by the absence of the three typical Northern species and all species of the genusLumbricus.