Dislocation of the sternoclavicular joint can be associated with life-threatening complications; therefore, a thorough knowledge of the ligaments contributing to sternoclavicular joint stability is essential for the clinician dealing with this anatomical area. The aim of our study was to examine the anatomy of the interclavicular ligament. We examined 50 human cadavers. The interclavicular ligament was identified in 90% of the specimens. The interclavicular ligament was located at the base of the sternal notch in 50% of the cases and connected the superior portions of the capsule of the sternoclavicular joints of each side. The interclavicular ligament connected with the posterior superior aspect of each medial end of the clavicle and with the fibers of the posterior and anterior interclavicular ligaments forming a continuous ligamentous layer. The mean length of this ligament was 2.1 cm, the mean width was 0.72 cm and the mean thickness was 0.36 cm. With the elevation of the shoulder joint and the abduction of the humerus, the interclavicular ligament remained lax. With the depression of the shoulder joint and the adduction of the humerus, this ligament became fully taut. As a result, the interclavicular ligament prevented the upward displacement of the clavicle during forceful depression of the humerus and the shoulder. The tensile force necessary for failure was >53.7 N/cm2 in all the specimens. These data may be useful to surgeons for instituting techniques for surgical procedures that reconstruct the sternoclavicular joint. Moreover, a future study aimed at evaluating the long-term consequences of surgical transection of this ligament may be in order.