The present invention provides a bicycle disc brake apparatus comprising a U-shape elastic plate having two ends connected to two ring portions; the ring portions comprising through holes; the U-shape elastic plate comprising two brake pads abutting the ring portions; two compression discs outside the U-shape elastic plate and adjacent to the ring portions, comprising protrusions penetrating the through holes to act on the brake pads, compression disc rotating slots away from the protrusions and first guiding tread surface in a first direction; two roller seats adjacent to the compression discs and comprising roller rotating slots adjacent to the compression disc rotating slots; rollers provided between the rotating slots; the roller rotating slots having second guiding tread surface in a second direction opposite to the first direction with protruding columns; two bearings mounted on the protruding columns; and two sealing gaskets sealed onto the bearings away from the roller seats.