Résumé: Three species of Cymothoidae (Crustacea, Isopoda), Emetha audouini, Ceratothoa collaris and C. steindachneri are here reported from Algeria. The presence of E. audouini and C. collaris is confirmed there and these two species are reported for the first time from Bejaia, Jijel and Annaba. Ceratothoa steindachneri is new for the Algerian fauna. Ceratothoa oestroides, C. parallela, C. oxyrrhynchaena, Anilocra frontalis, A. physodes and Nerocila bivittata are also recorded. New hosts are identified for C. parallela, C. steindachneri, A. frontalis and A. physodes as well as those of E. audouini. Three species of Aegidae, Aega rosacea, A. deshaysiana and Aega sp. are recorded. The presence of the first is reported for the first time in Algeria and that of the second is confirmed there. For each one of these species, potential preys are identified.