Abstract: An musculus orbicularis oris power measuring apparatus for quantitatively determining the power of the musculus orbicularis oris around the human mouth is provided. A force for closing the mouth lips is detected as an electric output signal by a load sensor shaped so as to be held between the lips. A maximum value of the load force as detected by the load sensor is sensed by a peak hold circuit and stored therein. The thus stored value is indicated either in an analog form or in a digital form by a peak value indicator.