The invention discloses a deep three-soft coal seam asymmetric tunnel supporting structure comprising a tunnel top support, a roadside support, and a tunnel bottom support; the tunnel top support comprises a metal net used for supporting the tunnel top, and top steel bar ladder beams, top anchor poles and top anchor cables used for reinforcing the tunnel top,; the roadside support comprises a high side support and a low side support, each of which comprises an electric welding plain net used for supporting the roadside, and side steel bar ladder beams and side anchor poles used for reinforcing the tunnel roadside; the high side support also comprises side cables; the tunnel bottom support comprises base angle anchor poles vertically and symmetrically arranged along the tunnel, wherein the base angle anchor poles are arranged on two side base angles formed by the tunnel bottom and the roadside, and the angle of depression is 45 degrees. The anchor-beam-net-cable combined support mode is employed; the anchor poles, anchor cables and steel bar ladder beams of the tunnel top and roadside can improve tunnel surrounding rocks stress states; the side cables are arranged so as to reinforce tunnel high side local support; the base angle anchor poles are arranged so as to effectively control the tunnel bottom heaves.