Nowadays, hypertension is a real scourge for public health. Objectives: The study consisted in evaluating the effects of aqueous extracts of Persea americana Mill leaves (Leucaceae) on both the vasomotility and the acute toxicity of the isolated rat aorta. Study of the effects of the aqueous extract of Persea americana leaves on isolated rat aorta: qualitative approaches to vasomotility and acute toxicity. The animals used in this study were adult albino rats of the Wistar type (Rattus Norvengicu, 150-250mg). The chemical composition of the extract was considered by phytochemical screening. The effect of the extract of the traditional healer pre-contracted with Potassium Chloride produces a slight temporary relaxation with each dose before contracting again and waiting for a value greater than the previous value. It is the same for this same extract of the traditional practitioner pre-contracted with Adrenaline, the organ relaxes then recontracts, and this with each dose of the extract administered. The DL50 showed that no signs of intoxication were observed in the treated animals. None mortality or oral toxicity was recorded in animals. Aqueous extracts prepared in the laboratory compared to traditional healer decoction cause relaxation of the aorta. Furthermore, the phytochemical screening revealed the presence of many antihypertensive components in the aqueous extract. Our study on the isolated rat aorta allowed us to observe a relatively more or less mild relative vasorelaxation. Others studies would be required for the plant to be designated for the development of an improved traditional medicine. Published by the International Journal of Biomolecules and Biomedicine (IJBB)