耳蜗（拉丁文，德文，英文：Cochlea）是内耳的一个解剖结构，它和前庭迷路一起组成内耳骨迷路。耳蜗的名称来源于其形状与蜗牛壳的相似性，耳蜗的英文名Cochlea，即是拉丁语中“蜗牛壳”的意思。耳蜗是外周听觉系统的组成部分。其核心部分为柯蒂氏器（拉丁文：Organon spirale.英文：Organ of Corti，德文：Corti-Organ），是听觉转导器官，负责将来自中耳的声音信号转换为相应的神经电信号，交送脑的中枢听觉系统接受进一步处理，最终实现听觉知觉。耳蜗的病变和多种听觉障碍密切相关。

The cochlea /ˈkɒk.lɪə/ (Ancient Greek: κοχλίας, kōhlias, meaning spiral or snail shell) is the auditory portion of the inner ear. It is a spiral-shaped cavity in the bony labyrinth, in humans making 2.5 turns around its axis, the modiolus. A core component of the cochlea is the Organ of Corti, the sensory organ of hearing, which is distributed along the partition separating fluid chambers in the coiled tapered tube of the cochlea. The name is derived from the Latin word for snail shell, which in turn is from the Greek κοχλίας kokhlias ("snail, screw"), from κόχλος kokhlos ("spiral shell") in reference to its coiled shape; the cochlea is coiled in mammals with the exception of monotremes.