The ileocolic vein is located within the digestive tract. It receives blood from the appendicular vein, and it drains oxygen-depleted blood from the ileum in the small intestine and the cecum and colon, parts of the large intestine.

From there, this deoxygenated blood flows to the superior mesenteric vein, which joins with the hepatic portal vein. As part of the venal circulatory system, all deoxygenated blood flows back to the lungs and the heart, where the circulatory system both begins and ends.

The ileocolic vein should not be confused with the ileocolic artery. Arteries and veins flow in opposite directions. The ileocolic artery delivers oxygen-rich blood to the ileum, cecum, and colon. Like its venal counterpart, the artery has a branch that serves the appendix.

Like many other parts of the venal system, the ileocolic vein may be subject to occlusion or clots. Although this is not common in the ileocolic vein, it is hard to accurately treat when it does occur. Surgical intervention and blood-thinning medications are frequently advised treatments.