The invasion extensity (EI) and invasion intensity (II) were studied in domestic birds in Republic of Moldova depending on maintenance technologies (complexes, farms, private sector) and it was established the parasitism by 18 malophagous species, 2 flea species and 2 gamasid acarian species. In hens (Gallus gallus domesticus) from private sector 9 malophagous species (Cuclotogaster heterographus, Eomenacanthus stramineus, Goniocotes gallinae, Goniocotes maculatus, Goniodes dissimilis, Lipeurus caponis, Menopon gallinae, Menacanthus cornutus, Menacanthus pallidulus,), 2 flea species (Ceratophylus gallinae, C. hirundinis) and 2 gamasid acarian species (Dermanyssus gallinae, D. hirundinis) were determined. In the structure of malophagian poliparasitism the species Eomenacanthus stramineus occupy the dominant position in all hen maintenance units. The invasion extensity in private sector constitute 62,5%, in farms – 35% and in complexes – 20%. Hen infection with malophagous, fleas and gamasid acarians occurs during the whole year, but a significant decreasing of infestation was recorded during summer (July-August).