AbstractFive critically endangered Iberian lynxes (Lynx pardinus) and 35 other sympatric carnivores (19 feral catsFelis catus, 12 Egyptian mongoosesHerpestes ichneumon, and 4 common genetsGenetta genetta) were analysed for helminths in Sierra Morena and Doñana area (southern Spain).Ancylostoma tubaeforme, which was believed to be harmful for lynx cubs according to a previous study, was present in the only lynx and in 53% of cats analysed in Doñana (80% in adult cats). Other species shared in both areas wereToxocara cati(1 lynx, 31% of cats),Joyeuxiella pasqualei(1 lynx, 21% of cats) andMesocestoidessp. (2 lynxes, 5% of cats). Only one mongoose was parasitized, harbouring larvae of two acantocephalan species not previously reported in the Iberian peninsula (Centrorhynchus(Sphaerirostris)lanceaandCentrorhynchus(Longirostris)undulatus). Feral cats may be a reservoir for hookworms and other helminths affecting the Iberian lynx. In contrast, mongooses and genets may not play a role in the epidemiology of these species.