Chaetophractus villosus and Dasypus hybridus are the most widespread and abundant armadillos inhabiting the Pampas grasslands. Studies on the parasitic fauna from an ecological perspective are scarce in both species. We describe and compare the component communities of C. villosus and D. hybridus in the Pampas ecoregion of Argentina and analyse if the composition and structure of the parasitic communities of these host species reveal trophic behaviour and/or habitat use. In the population of C. villosus 10 species of helminths were found, namely Ancylostoma caninum , Aspidodera fasciata , Aspidodera scoleciformis , Mazzia bialata , Moennigia celinae , Orihelia anticlava , Strongyloides sp., Trichohelix tuberculata (Nematoda) and Mathevotaenia sp. (Cestoda), whereas in the population of D. hybridus four species were found, A. fasciata , Delicata abbai , Pterygodermatites chaetophracti and Strongyloides sp. Only A. fasciata and Strongyloides sp. were present in both species. Prevalences and intensities were similar in Strongyloides sp. In A. fasciata , however, there were differences regarding mean intensity. Diversity was higher in C. villosus than in D. hybridus. The differences may be related to the diet, behaviour, evolutionary histories or immune response of the species studied. A combination of several of these factors would possibly influence the composition of their parasitic fauna.