The utility model specifically discloses an air leakage control system of an air pre-heater. The air leakage control system comprises a driving motor; the driving motor is provided with two forward contactors; the two forward contactors are in series connection and then are connected with a main circuit of the driving motor; for the two contactors, main contacts are in parallel connection, normally closed contacts are in parallel connection, normally opening contacts are in series connection, one end of each of the main contacts in parallel connection is connected with a backward contactor, and the other end of each of the main contacts in parallel connection is connected with a power supply end; the two ends of the normally closed contacts in parallel connection are connected with the power supply end; the two ends of the normally opening contacts in parallel connection are connected with the power supply end. According to the air leakage control system of the air pre-heater, which is disclosed by the utility model, the reliability of an automation device of a sector plate of the air pre-heater is improved; the operation safety of the automation device of the sector plate of the air pre-heater is ensured; the overhaul and the maintenance are convenient.