The invention belongs to the technical field of construction energy dissipation structures and relates to a self-resetting buckling-restrained brace which comprises a central positioning plate and second-stage buckling-restrained units located on the left side and the right side. Each second-stage buckling-restrained unit comprises a connecting joint, a supporting
core component, an outer sleeve steel
pipe, a sliding bearing plate, a
fixed bearing plate, a stable
steel bar, a
steel frame support, a belleville spring and a friction plate. The supporting
core component, the sliding bearing plateand the stable
steel bar are sequentially connected and slide in the outer sleeve steel
pipe. The middle part of the supporting
core component penetrates through the outer sleeve steel
pipe; the outer end of the supporting core component is fixedly connected with the connecting joint; the
fixed bearing plate, the
steel frame support and the central positioning plate are sequentially connected, and the inner end of the stable
steel bar penetrates through the
fixed bearing plate; the friction plate in contact with the stable steel bar is arranged between the fixed bearing plate and the centralpositioning plate; and the compressed belleville spring sleeves outside the stable steel bar. The invention further relates to an energy dissipation method of the self-resetting buckling-restrained brace. The structure is simple, the
bearing capacity of a main body structure is increased, and the self-resetting capacity is achieved.