The giant armadillo (Priodontes maximus) is the largest extant representative of the order Cingulata. Information on the parasites and diseases affecting this species is scarce. Four female and one male ticks were collected from two wild-caught, adult giant armadillos from the northern Pantanal, Mato Grosso, Brazil. All of them were identified as Amblyomma cajennense. This is the first report of A. cajennense in giant armadillos. Considering the low host specificity of this ixodid tick that may act as vector of pathogens, and the sustained encroachment of domestic animals into wildlife habitat, the risk of disease transmission from cattle to this threatened armadillo should be evaluated.