The difference between arteries and veins is as follows: 1. The main difference is that arteries are issued by the heart to supply blood to the whole body, while veins are the vessels that collect blood from the whole body back to the heart. 2. The walls of arteries are thicker and more elastic than the walls of veins and have higher pressure, which is the only way to withstand the pressure of the arteries within the normal blood vessels. Veins have thinner walls and larger lumens compared to arteries, and veins are often accompanied by valves, mainly to prevent regurgitation of blood within the veins. 3, blood within arteries has a higher oxygen content and is bright red in color. The blood in the veins has a lower oxygen content and is dark red in color.