Disc brake system and controlling method thereof

A method of controlling a disc brake system, the disc brake system comprising:

• a main braking part configured to slide and move a pair of main pads respectively disposed on both side surfaces of a disc in a direction of an axis of the disc and generate a main braking force by friction between the both side surfaces of the disc and the main pads;
• an auxiliary braking part configured to slide and move an auxiliary pad disposed at a side of an outer circumferential surface of the disc in a radial direction of the disc and generate an auxiliary braking force by friction between the outer circumferential surface of the disc and the auxiliary pad;
• and
• a controller configured to activate the main braking part in response to an input value generated based on a pedal force of a brake pedal measured by a sensor,
• wherein the controller activates or deactivates the auxiliary braking part by comparing the input value and a preset threshold value.