Abstract: Recently, there has been growing interest in the traditional cures of livestock diseases. This is because industrially produced drugs are too expensive for some sectors of the farming community especially in the developing world. Medicinal plants are often cheaper and more easily available than the commercially produced drugs. The self-help study in form of traditional medicines (especially from medicinal plants), offer a way out by making use of resources available within the communities themselves. Despite the steady increase in demand for herbal medicines over the past decade worldwide, a great majority of herbal products are not pharmacologically assessed for their quality, safety and efficacy, nor are they licensed as medicine. In this study some of the medicinal plants used by the Banyankole (an ethnic group with a long history of cattle-keeping and the use of medicinal plants) have been tested in vitro using the Ascaris model. Seven plants were studied (Vernonia amygdalina, Cassia didymobotrya, Rhoicissus tridentata, Phytolacca dodecandra, Euphorbia hirta, Aspilla africana and Cymbopogon nardus). Aspillia africana and Cymbopogon nardus did not show anthelmintic activity in this test system. The other five showed anthelmintic activity (Vernonia amygdalina, Cassia didymobotrya, Rhoicissus tridentata, Phytolacca dodecandra and Euphorbia hirta). Extracts of Vernonia amygdalina, Rhoicissus tridentata and Cassia didymobotrya showed higher activity than Euphorbia hirta and Phytolacca dodecandra (Vernonia amygdalina (ED₅₀) of 3.533 mg mL ¹, Rhoicissus tridentata (ED₅₀) of 4.355 mg mL ¹ and Cassia didymobotrya (ED₅₀) of 4.880 mg mL ¹; Euphorbia hirta (ED₅₀) of 5.866 mg mL ¹ and Phytolacca dodecandra (ED₅₀) of 7.151 mg mL ¹). Further studies on the five plants are needed. Phytochemical analysis to determine the active principles that are responsible for anthelmintic activity are urgently called for. This would help in identifying the spectrum of activity of the extracts as well as determining their mechanism of action. Studies should also be carried out on these plants to determine their toxicity and also their effect on other helminthes apart from Ascaris.