Disclosed is an automatic adjustment system for a steering wheel provided in a process line to support wheel alignment operation of a vehicle mounted with an OBD, includes a scanner for recognizing a vehicle identification number entered into the process line; an antenna that connects the OBD of the vehicle with the wireless diagnosis communication to transmit and receive data; a robot moves a vision sensor mounted on the front end portion thereof to the shooting position of the steering wheel in the vehicle through the attitude control, when the vehicle is seated in a centering position; and a control apparatus that analyzes the shooting image of the vision sensor to calculate the current distorted angle of the steering wheel and initialize by inputting the current distorted angle of the steering wheel to the steering angle sensor via the diagnosis communication connected with the OBD of the vehicle.