The brachiocephalic artery, brachiocephalic trunk, or innominate artery is an artery of the mediastinum that supplies blood to the right arm, head, and neck.

It is the first branch of the aortic arch. Soon after it emerges, the brachiocephalic artery divides into the right common carotid artery and the right subclavian artery.

There is no brachiocephalic artery for the left side of the body. The left common carotid artery and the left subclavian artery come directly off the aortic arch. Despite this, there are two brachiocephalic veins.

The brachiocephalic artery arises on a level with the upper border of the second right costal cartilage from the start of the aortic arch on a plane anterior to the origin of the left carotid artery. It ascends obliquely upward, backward, and to the right to the level of the upper border of the right sternoclavicular articulation, where it divides into the right common carotid artery and right subclavian arteries. The artery then crosses the trachea in front of it obliquely from the left to the right, roughly at the middle of the trachea or the level of the ninth tracheal cartilage.

The brachiocephalic artery has relation with:

The thymus typically sits atop the brachiocephalic artery, and it separates the artery from the posterior surface of the manubrium of sternum.

The thyroid ima artery ascends in front of the trachea to the lower part of the thyroid, which it supplies.

The innominate artery usually gives off no branches, but occasionally a small branch, the thyroid ima artery, arises from it. Other times, it gives off a thymic or bronchial branch.