Angiogenesis is a vital process through which new blood vessels proliferate from pre-existing vessels. This study was conducted to determine the antiangiogenic potential Manihot esculenta Crantz leaves ethanolic extract on the Chorioallantoic Membrane (CAM) of duck embryos. Concentrations of 100%, 50% and 10% leaves extract were utilized for the treatment of the experimental group. Distilled water, 95% ethanol, 0.05% Retinoic acid, and no treatment added were used for the controlled group. Fifty-six one-day old eggs were pre-incubated for 10 days; treatments were applied on the 10th day, and incubated further for two days. The CAM embryo was removed from the shell on the 12th day and vessel branch points were manually counted. Quantifcation of the vessel branch points among the experimental treatments were statistically signifcant, showing the antiangiogenic potential of the ethanolic extract of M. esculenta leaves. The angiosuppressive activity of pure ethanolic extract of M. esculenta leaves is even comparable to retinoic acid, which is a known angiogenic inhibitor. The antioxidants, lignans and linamarin found on the leaves of M. esculenta from scientifc literatures might be attributed to the angiosuppressive potential of the plant. Based on the results, the study could lead to new direction in the feld of phytochemistry in the development of blood vessel inhibitory drugs.