It is presumed that ayurvedic drugs have lesser side effects as compared to allopathic drugs. For the safety to use these plants and preparations (gel and powder forms), the medicinal plants need to be evaluated for their toxicity. The aim of this study was to test the acute toxicity of three medicinal plants, Terminalia bellerica (Gertn.) Roxb. fruits, Moringa pterigosperma (Gaertn) leaves, Cassia tora Linn.leaves. The acute toxicity study was studied on Swiss mice with a dose of 3 and 5 g/Kg body weight orally. The single administration exposure of the whole plant powder in the form of aqueous slurry on Swiss mice was carried out and the exposure route was oral with water as a vehicle. The observations of changes in body weight, food and water intake as well as cage side observations were reported. The plants were found to be nontoxic