In the years 2002-2003 research was carried out concerning ethnomedicine in the Acquapendente district (Viterbo, Latium, central Italy), an area so far less frequently studied from the perspective of plant folk traditions. The district, from the ethnobotanical point of view, shows traces of the influences of the neighbouring regions. In this study 96 plant entities are described, belonging to 45 families, of which 64 are employed in human medicine, 15 in veterinary medicine, 22 in the feeding of domestic animals, 5 as antiparasitics and 5 for other uses. Some medicinal uses are linked to beliefs or residual forms of magic prescriptions (11 plants). Amongst the more notable uses the most interesting are those of: Verbena officinalis (rheumatic pains, wounds), Juglans regia (antiparasitic use for cheeses), Santolina etrusca (antimoth use), Stellaria media and Lupinus albus (birdseed for poultry and fodder for lambs), and Thymus longicaulis subsp. longicaulis (used to curdle milk).