We investigated potential interspecific predation between two invasive crustacean species, currently widespread and co-occurring in European inland waters: the Ponto-Caspian amphipod Dikerogammarus villosus (Gammaridae) and the North American spiny-cheek crayfish Orconectes limosus (Cambaridae). We evaluated interactions of adult specimens of D. villosus and juvenile O. limosus (from the 3rd developmental stage – DS) under conditions with and without feeding.