For measuring hardness of an object, a measurement apparatus is pushed against the object and a degree of hardness calculation system calculates hardness based on information from the measurement apparatus. The measurement apparatus includes an acceleration sensor which outputs first information of acceleration of a contact area of the measurement apparatus, and a second sensor, such as a magnetic sensor or a pressure sensor, which outputs second information based on pressure applied to the contact area. The degree of hardness calculation system generates a second-derivative waveform by twice differentiating a waveform based on the output of the second sensor, compares the second-derivative waveform and the information of acceleration from the acceleration sensor, and calculates hardness of the object based on the comparison result.