The invention provides an automobile power steering control device with a fault-tolerant function and a control method. The control device comprises an acquisition unit, an ideal yaw angle speed calculation unit, a subtracter unit, a yaw angle speed control unit, a motor fault diagnosis unit and a fault-tolerant control strategy unit. The rotation speed and a current signal of a wheel hub motor are acquired in real time through the control device, fault diagnosis is conducted on the wheel hub motor, and a fault signal vector is generated; and torque of the motor is redistribute according to the fault signal vector and a target corner calculated through the ideal yaw angle speed calculation unit, or a steering servo motor is used to enable an automobile to steer according to the desired trajectory. According to the automobile power steering control device with the fault-tolerant function and the control method, faults of the wheel hub motor can be detected in real time, and when the faults occur, the fault-tolerant function is achieved through effective control means, so that the reliability of a steering system and the stability and safety during automobile driving are improved.