A back plate structure comprises a back plate body, at least a supporting beam and a plurality of heat dissipation members, wherein the supporting beam is fixed on a back of the back plate body and the heat dissipation members are disposed on the supporting beam. The supporting beam has a central protrusion portion and a peripheral portion. The heat dissipation members are disposed on an upper surface of the peripheral portion or on a sidewall of the central protrusion portion or into an inner portion of the central protrusion portion. Because the heat dissipation members are disposed on the supporting beam, the heat dissipation area of the present invention can be increased and therefore the heat dissipation efficiency of the plasma display apparatus can be effectively promoted. Therefore, the service life of the plasma display apparatus can be increased and also the display performance thereof can be enhanced.