The invention relates to a fiber concrete beam with a special-shaped mid-span section, which can satisfy the construction requirements of rigidity and strength in the normal service state of a structure and has sufficiently high ductility in an earthquake, so as to reduce the damage degree of a building, and belongs to the field of anti-seismic and shock absorption technologies of structural engineering. On the condition that a mid-span can bear sufficient normal carrying capacity, such as a shearing force and a bending moment, a high-ductility cast-in-situ glass fiber concrete is constructed inside the special-shaped mid-span section to improve the ductility of the whole beam body, realize a high ductile failure mode of the beam body and finally realize the damage from the mid-span; and an unbonded prestressing steel strand is constructed inside the mid-span section to ensure that the beam body satisfies the design standard of carrying capacity and also realize the resetting of the beam body in the case that he beam body shits and deforms in an earthquake. By using the high-ductility concrete, the automatic restoration of the beam is improved through a prestressing reinforcing steel bar in the plastic destruction process of the mid-span of the beam, thus the shock absorption and the energy dissipation of a beam structure are realized, and finally the shock absorption and anti-seismic functions of the whole building are realized.