To provide a monitoring method for the durable period of a ceramic brake disc used in an automobile without using any additional load sensor.

The braking and running dynamic characteristics, for example, a running speed, brake pressure and braking time, are detected, and individual braking process brake pressures are added to the delection, and the obtained sum is compared with the preset reference value, and if the sum is exceeding the reference value, an optical and/or acoustical instruction is given to a driver.