The invention relates to a backup rescue system of an elevator. When the elevator stops between two floors due to power outage, or an internal fault of a control cabinet, or other line faults, the backup rescue system of the elevator can be started to drive the elevator to reach a nearby floor, a door can be opened, and passengers can be rescued. The backup rescue system of the elevator is independent of an existing control system of the elevator, and can automatically drive the elevator to reach the nearby floor according to the condition of the load of a lift car after being started, an internal contracting brake power source can be automatically cut out when the elevator reaches a door area, the door can be opened, and trapped persons can be rescued. The backup rescue system of the elevator is applicable to elevators with machine rooms and elevators without machine rooms, and cannot be influenced by arrangement of a shaft way, difficulty of rescue operation is low, rescue can be safely and reliably carried out under various conditions of elevator faults, and the backup rescue system of the elevator is simple in structure, easy to maintain, high in reliability, small in occupied area and low in cost.