Blood donation is drawn from veins, arterial blood is rich in oxygen, if the arterial blood is drawn, it may lead to local hypoxia of the body, while venous blood is almost free of oxygen, there is no danger. Arterial blood is located in the surface layer of the body, the blood flow is slow, easy to draw, arterial location is generally deeper, below the dermis, the vessel wall is thicker, not easy to draw, and the arterial pressure is high, not easy to stop bleeding, difficult to operate, the difference between arterial blood and venous blood is as follows: 1, arterial blood is bright red, venous blood is dark red; 2, arterial blood flows in the arteries, venous blood flows in the veins; 3, arterial blood transports nutrients and oxygen, venous blood transports waste and carbon dioxide; 4, arterial blood is rich in oxygen, venous blood transports waste and carbon dioxide. Venous blood carries waste and carbon dioxide; 4. Arterial blood flows from the heart to all organs of the body, and venous blood flows from all organs of the body back to the heart; 5. Arterial blood flows quickly because the heart gives strong pressure, and venous blood flows slowly because it depends on the strength of the valves to return to the heart; 6. Arterial blood puts great pressure on the blood vessels, and venous blood puts little pressure on the blood vessels.