A dual-core self-centering buckling-restrained brace includes a core unit, a restraining unit clamping the core unit therein, a middle sleeve disposed around the an energy dissipating section of the core unit and the restraining unit and having an end welded to one end of the core unit, an outer sleeve disposed around the middle sleeve and having an end welded to the other end of the core unit, two inner plates disposed respectively at two ends of the restraining unit, two outer plates disposed respectively at two ends of each of the middle sleeve and said outer sleeve, at least one first tensing member connecting the first inner plate to the second outer plate, and at least one second tensioning element connecting the first outer plate to the second inner plate.