A disc brake apparatus including combined generation and electric operation means comprising: a disc unit including a stationary plate, which is made of a nonmagnetic material and includes a plurality of coil elements (111 and 111'), which are radially arranged about a center of the stationary plate so as to be exposed from two lateral sides of the stationary plate, the stationary plate being fixed to a vehicle body and being disposed around a drive shaft so as to prevent rotational interference with the drive shaft, and a pair of rotating plates (120 and 120'), which are made of a nonmagnetic material and are coupled to the drive shaft via a key so as to be rotated together with the drive shaft at two lateral sides of the stationary plate, characterised in that the pair of rotating plates (120 and 120') being provided on surfaces thereof that face the stationary plate with a plurality of magnets (121 and 121'), which are radially arranged, and being elastically supported by respective compression springs, wherein electrical power is generated by charges applied to the coil elements (111 and 111') and stored in a battery; a Hall sensor, which is disposed close to the rotating plates (120 and 120') so as to detect a voltage caused by magnetic fields generated by the magnets (121 and 121') due to actuation of a brake pedal, the Hall sensor allowing current stored in the battery to be applied to the coil elements (111 and 111') so as to electromagnetize the coil elements (111 and 111') such that a polarity of the coil elements (111 and 111') and a polarity of the magnets (121 and 121') of the rotating plates (120 and 120') interact with each other to provide braking force caused by attractive force between the rotating plates (120 and 120') depending on the detected voltage; and a braking unit, which is disposed so as to surround peripheries of the rotating plates (120 and 120') at two outer lateral sides of the rotating plates (120 and 120'), the braking unit being configured to press the rotating plates (120 and 120') to thus provide braking force caused by frictional force therebetween to the rotating plates (120 and 120') when the brake pedal is actuated beyond an acceptable output range of the Hall sensor, wherein the Hall sensor is configured such that a distance between the Hall sensor and the magnets (121 and 121') decreases to thereby increase a voltage detected by the Hall sensor with increase of pressing force of the brake pedal. a disc unit including a stationary plate, which is made of a nonmagnetic material and includes a plurality of coil elements (111 and 111'), which are radially arranged about a center of the stationary plate so as to be exposed from two lateral sides of the stationary plate, the stationary plate being fixed to a vehicle body and being disposed around a drive shaft so as to prevent rotational interference with the drive shaft, and a pair of rotating plates (120 and 120'), which are made of a nonmagnetic material and are coupled to the drive shaft via a key so as to be rotated together with the drive shaft at two lateral sides of the stationary plate, characterised in that the pair of rotating plates (120 and 120') being provided on surfaces thereof that face the stationary plate with a plurality of magnets (121 and 121'), which are radially arranged, and being elastically supported by respective compression springs, wherein electrical power is generated by charges applied to the coil elements (111 and 111') and stored in a battery; a Hall sensor, which is disposed close to the rotating plates (120 and 120') so as to detect a voltage caused by magnetic fields generated by the magnets (121 and 121') due to actuation of a brake pedal, the Hall sensor allowing current stored in the battery to be applied to the coil elements (111 and 111') so as to electromagnetize the coil elements (111 and 111') such that a polarity of the coil elements (111 and 111') and a polarity of the magnets (121 and 121') of the rotating plates (120 and 120') interact with each other to provide braking force caused by attractive force between the rotating plates (120 and 120') depending on the detected voltage; and a braking unit, which is disposed so as to surround peripheries of the rotating plates (120 and 120') at two outer lateral sides of the rotating plates (120 and 120'), the braking unit being configured to press the rotating plates (120 and 120') to thus provide braking force caused by frictional force therebetween to the rotating plates (120 and 120') when the brake pedal is actuated beyond an acceptable output range of the Hall sensor, wherein the Hall sensor is configured such that a distance between the Hall sensor and the magnets (121 and 121') decreases to thereby increase a voltage detected by the Hall sensor with increase of pressing force of the brake pedal.