Objective: Angiogenesis is a key process in the promotion of cancer and its metastasis. Many natural health products inhibit angiogenesis. Because of the lack of molecular studies on anti-tumor and anti-angiogenic effects of shallot (Allium ascalonicum); except a few clinical studies on other shallot properties, such as the anti-proliferative effect of shallot chloroformic extract on two tumor cell lines, the present study focuses on the anti-angiogenic effect of aqueous shallot extract using an aorta ring model. Materials and Methods: Aortic rings were obtained by cross-sectioning, at 1-2 mm intervals, the thoracic aorta of 4-8 weeks old Wistar male rats and cultured them in a thin <font><font>drop</font></font> of type I collagen gel. After 3 days of culturing and first sprouting, the extract of A. ascalonicum (from 25 to 800 μg/ml) was added to cultures. The results of anti-angiogenic activity were investigated by microscope. The cytotoxicity of extract at different doses on HUVECs was measured by trypan blue assay. Results: The results showed that the shallot extract has suitable anti-angiogenic effect in a range of 50 to 800 μg/ml, but in 25 μg/ml, the extract has no considerable effect. In addition, a tangible cytotoxic effect on endothelial cells at the above mentioned doses was observed. Conclusion: Our study showed that aqueous extract of A. ascalonicum bulbs has noticeable anti-angiogenic activity without toxic effect on the cells in doses that ranged from 50-800 μg/ ml. Therefore, A. ascalonicum can be a potential candidate for further investigations used in angiogenesis-related pathologic conditions.