Disclosed is a mirror-bracket-type overall tunnel bottom arch-shaped lining and a drainage system thereof. The mirror-bracket-type overall tunnel bottom arch-shaped lining and the drainage system thereof can eliminate the effect of ground water on the bottom structure of a tunnel lining, can effectively solve the problems of the upward floating deformation of the tunnel inverted arch or the cracking damage of the tunnel bottom structure in ground water development areas, areas whereground water is irregularly influenced by the seasons or karst area, so as to ensure the stability and safety ofthe tunnel construction and operation. The bottom of an arch wall secondary lining structure is provided with a mirror-bracket-type overall tunnel bottom building body, the upper portions of the two transverse ends of the mirror-bracket-type overall tunnel bottom building body are connected with the bottoms of the two sides of the arch wall secondary lining structure to serve as bearing foundations of the arch wall secondary lining structure, and a center upper portion platform is provided with ballast beds to serve as bearing structures of train load. Two sides of the mirror-bracket-type overall tunnel bottom building body are provided with longitudinal cavities, and the lower portion is an arc-shaped cavity. A tunnel bottom drainage system communicates with the arch-shaped cavity, a ballast bed hydrops draining system communicates with the longitudinal cavities and the arc-shaped cavity, and an arc wall range drainage system communicates with the longitudinal cavities.