The invention discloses a rear rack assembly in a wind generating set. The rear rack assembly comprises a rear rack welding part and a rear rack accessory. The rear rack seaming comprises a main rackconnecting plate, an upper panel, a lower panel, a left side plate, a right side plate, a generator front support seaming, a generator rear support seaming, a cantilever crane mounting support seaming, a cabin bracket mounting plate, a cabin cabinet mounting bracket, a left side walking channel mounting bracket, a right side walking channel mounting bracket and the like; and the rear rack accessory comprises a generator rotor outgoing cable, a rotor outgoing cable mounting rack, a generator stator outgoing cable, a stator outgoing cable mounting rack, a generator auxiliary junction box outgoing cable mounting rack, a gear box cooling system pipeline and a grid type cable bridge. The rear rack assembly not only is used for supporting key components such as a generator, a cabin control cabinet I, a cabin control cabinet II, a cabin bracket and a walking channel cover plate, but also is used for fixing components such as an outgoing cable and a cable mounting frame, and has the characteristics of simple structure and convenience in mounting.