A bicycle disc brake apparatus, comprising: a U-shape elastic plate comprising a connection portion having two ends connected to two ring portions thereof respectively; each one of said ring portions having a through hole formed thereon; two brake pads provided in an internal of said U-shape elastic plate and spaced apart from each other; wherein each one of said brake pads abuts each one of said ring portions respectively; two compression discs arranged at an external of said U-shape elastic plate and adjacent to each one of said ring portions of said U-shape elastic plate; each one of said compression discs comprising a protrusion penetrating through said through hole of each one of said ring portions for acting on each one of said brake pads correspondingly; wherein each one of said compression discs comprises a plurality of compression disc rotating slots provided on one side of the compression disc away from said protrusion and arranged spaced apart from each other, and each one of said compression disc rotating slots comprises a first guiding tread surface facing toward a first direction; wherein the compression disc rotating slots are used for partially accommodating rollers; two roller seats arranged adjacent to each one of said compression discs; each one of said roller seats comprising a plurality of roller rotating slots corresponding to said plurality of compression disc rotating slots in number and provided on one side of said roller seats adjacent to said compression discs; a roller provided between each one of said roller rotating slots and each one of said compression disc rotating slots; wherein each one of said roller rotating slots comprises a second guiding tread surface facing toward a second direction opposite from said first direction, and each one of said roller seats comprises a protruding column arranged axially on one side of each one of said roller seats away from each one of said compression discs correspondingly; two bearings having a ring shape, mounted on said protruding column of each one of said roller seats respectively and abutting a surface of one side of each one of said roller seats away from said roller rotating slots; and two sealing gaskets placed onto each one of said bearings respectively on one side of said bearings away from said roller seats correspondingly. a U-shape elastic plate comprising a connection portion having two ends connected to two ring portions thereof respectively; each one of said ring portions having a through hole formed thereon; two brake pads provided in an internal of said U-shape elastic plate and spaced apart from each other; wherein each one of said brake pads abuts each one of said ring portions respectively; two compression discs arranged at an external of said U-shape elastic plate and adjacent to each one of said ring portions of said U-shape elastic plate; each one of said compression discs comprising a protrusion penetrating through said through hole of each one of said ring portions for acting on each one of said brake pads correspondingly; wherein each one of said compression discs comprises a plurality of compression disc rotating slots provided on one side of the compression disc away from said protrusion and arranged spaced apart from each other, and each one of said compression disc rotating slots comprises a first guiding tread surface facing toward a first direction; wherein the compression disc rotating slots are used for partially accommodating rollers; two roller seats arranged adjacent to each one of said compression discs; each one of said roller seats comprising a plurality of roller rotating slots corresponding to said plurality of compression disc rotating slots in number and provided on one side of said roller seats adjacent to said compression discs; a roller provided between each one of said roller rotating slots and each one of said compression disc rotating slots; wherein each one of said roller rotating slots comprises a second guiding tread surface facing toward a second direction opposite from said first direction, and each one of said roller seats comprises a protruding column arranged axially on one side of each one of said roller seats away from each one of said compression discs correspondingly; two bearings having a ring shape, mounted on said protruding column of each one of said roller seats respectively and abutting a surface of one side of each one of said roller seats away from said roller rotating slots; and two sealing gaskets placed onto each one of said bearings respectively on one side of said bearings away from said roller seats correspondingly.