The intermediate status of hybrids regarding to parental species in morphology, ecology and trophic biology was often documented in nature and confirmed empirically. Concerning host-parasite associations, the host-parasite co-adaptation is interrupt due to interspecific hybridization which may lead to the changes of the structure of parasite communities in the hybrids when compared to parental species. In addition, it is hypothesized that the maternal ancestry of hybrids affects monogenean infection. The monogenean parasites with specific co-adaptation to their hosts represent the suitable model for the investigation of the effect of hybridization on host specificity and host-parasite interaction. The aim of this study was to investigate the effects of the hybridization and maternal origin of hybrids on the composition of monogenean parasite communities in the hybridizing system of common bream (Abramis brama) and silver bream (Blicca bjoerkna). Pure lines of both species were prepared as well as F1 hybrids with different maternal ancestry were obtained by the artificial cross-breeding. Fish were infected by monogenean parasites from source specimens of both parental species. Maternal origin of the hybrids was checked using cytochrome b sequences. Experimental work proceeded in two consecutive years (2015 and 2016). Hybrid offspring possess higher parasite species richness when compared to common bream and silver bream. Monogenean abundance was higher in parental species. Hybrids with the maternal origin of common bream were less parasitized than the other fish groups. Interruption of the system of co-adapted genes might lead to the higher monogenean richness and presence of the parental species-specific parasites of the both parental species in the hybrids. The species-specific composition in parasite communities of hybrid fish with both maternal origins was shifted to the parasites of the silver bream. This seems to suggest the different degree of the host-parasite co-adaptation in A. brama and B. bjoerkna.