气管（trachea）是连接喉部与肺部的信道，腹侧由软骨环组成，背侧由平滑肌所组成，向上以声带为出口，向下分支称之为支气管（bronchus）。组成气管的软骨为透明软骨。

The trachea, colloquially called the windpipe, is a tube that connects the pharynx and larynx to the lungs, allowing the passage of air, and so is present in almost all air-breathing animals with lungs. Only in the lungfish, where the lung is connected to the pharynx and the larynx, is it absent. The trachea extends from the larynx and branches into the two primary bronchi. At the top of the trachea the cricoid cartilage attaches it to the larynx. This is the only complete ring, the others being incomplete rings of reinforcing cartilage. The trachealis muscle joins the ends of the rings and these are joined vertically by bands of fibrous connective tissue – the annular ligaments of trachea. The epiglottis closes the opening to the larynx during swallowing.