An in-ear measuring device is cooperated with an external auditory canal and includes a headphone body, a variable mechanism and a sensing module. The variable mechanism is connected with the headphone body and in close connection with the external auditory canal. The sensing module is disposed in the variable mechanism and has a light-emitting element and an optical sensing element. The light-emitting element emits a light toward to the external auditory canal and received by the optical sensing element to generate a sensing signal.一種耳道式量測裝置與一外耳道配合,並包括一耳機本體、一可變機構以及一感測模組。可變機構與耳機本體連接,並與外耳道緊密結合。感測模組設置於可變機構內,並具有一發光元件及一光學感測元件,發光元件發出一光線射向外耳道,且被光學感測元件所接收而產生一感測訊號。1‧‧‧耳道式量測裝置11‧‧‧耳機本體12‧‧‧可變機構121‧‧‧耳塞墊122‧‧‧彈性件13‧‧‧感測模組14‧‧‧聲音模組15‧‧‧控制模組16‧‧‧運算模組18‧‧‧耳套墊
