A component measuring device (10) comprises a sound-volume change-over switch (40) for switching the volume of sound representative of a measurement value of a predetermined component in a biological fluid, the sound being outputted from a speaker (58). The sound-volume change-over switch (40) switches the volume of the sound outputted from the speaker (58) at least between a weak whisper-like volume level and a normal volume level. In the whisper-like volume level, noise level falls within the range from 36 dB to 53 dB, the noise level being measured in an anechoic chamber by a noise level meter (70) with the component measuring device (10) being separated from a microphone (72) of the noise level meter (70) by a distance of 3 cm. In the normal volume level, noise level is 50 dB or more, the noise level being measured in the anechoic chamber by the noise level meter (70) with the component measuring device (10) being separated from the microphone (72) of the noise level meter (70) by a distance of 50 cm.成分測量裝置(10)具備用以切換從揚聲器(58)被輸出之語音的音量切換開關(40)，該語音係表示體液之特定成分的測量值，音量切換開關(40)係將從揚聲器(58)被輸出之語音至少切換成微弱之耳語音量和一般音量的開關。該耳語音量在無響室中，當成分測量裝置(10)和噪音計(70)之麥克風(72)之距離為3cm時，藉由噪音計(70)所測量到之噪音位準在36dB~53dB之範圍內，一般音量在無響室中，當成分測量裝置(10)和噪音計(70)之麥克風(72)之距離為50cm時，藉由噪音計(70)所測量到之噪音位準則在50dB以上。
