[Object] It is possible to determine whether or not a device is mounted at a position suitable for measuring biological information, thereby making it possible to perform measurement at an optimal position and ensure certain measurement accuracy. Provide a measuring device. SOLUTION: A light emitting element for emitting measurement light of a predetermined wavelength, a light receiving element for receiving return light through which a measurement light passes through an object, and attachment to an object based on the received light quantity of return light in the light receiving element. The apparatus further includes a mounting determination unit that determines a state, and a measurement point determination unit that determines whether the measurement point is good or bad based on the received light amount of return light when the mounting determination unit determines that the object is correctly mounted. [Selected figure] Figure 4【課題】生体情報の測定に適した箇所に装着されているか否かの判定が可能であり、これによって、最適な位置での測定を可能とし、一定の測定精度を確保することができる生体情報測定装置を提供する。【解決手段】所定波長の測定光を発光する発光素子と、測定光が被検体を経由したもどり光を受光する受光素子と、受光素子における、もどり光の受光光量に基づいて被検体への装着状態を判定する装着判定部と、被検体に正しく装着されていると装着判定部が判定したときに、もどり光の受光光量に基づいて測定箇所の良否を判定する測定箇所判定部とを備える。【選択図】図４
