胸骨（Sternum）是胸腔中前方一块扁平，剑状的骨，接有肋 。

因为其外形如此，故其拉丁文中被名为剑，其三部分为

胸骨柄上部的颈静脉切迹（Incisura jugularis）可在体表触及，此乃颈部的下界。而两边的凹陷则是与两边锁骨(Clavicula)连接的关节面。关节面下第一肋切迹则是第一肋的连接处。

第二肋则连接在胸骨柄与胸骨体的接合处，3到7肋接于胸骨体的切接。

男性的胸骨较女性的要窄小。

The sternum or breastbone is a long flat bone shaped like a necktie located in the center of the chest. It connects to the ribs via cartilage, forming the front of the rib cage, and thus helps to protect the heart, lungs,and major blood vessels from injury. The sternum consists of three regions: the manubrium, the body, and the xiphoid process.