The paper presents the diagnosis of 4 new Bathynella species found in Romania: B. paranatans nov. sp., B. boteai nov. sp., B. motrensis nov. sp. and B. plesai nov. sp.; a discussion on B. cf. scythica Botosàneanu et Damian is also given. The morphological features which were used are the general and the fine structure of the genital pereiopode of the male (Pl. 5—8), the chaetotaxy of the maxillula, maxilla, thoracic appendages, uropods and furca. The presence of the distal (coxal) epipodite on the first pereiopod in B. paranatans nov. sp., distinguishes this species from the others (Pl. 1—4). The true taxonomical value of the VIIIth pereiopod of the male is pointed out, which - at least in the case of these species - shows, by its general structure, the relationships, the heterogeneous morphology of the anterior plate (PI. 5- 8, a), marking the speciation.