Abstract: A vehicle side obstacle detecting and warning method is applied on a vehicle. The vehicle side obstacle detecting and warning method includes providing a measuring step for measuring a dataset of the vehicle. The vehicle side obstacle detecting and warning method includes providing a detector installing step for positioning a plurality of detectors between the front wheel and the rear wheel according to the maximum inner wheel difference area. The vehicle side obstacle detecting and warning method includes providing a detected area adjusting step for adjusting a detecting distance or a positioning angle of at least one of the detectors to form a detected area. The vehicle side obstacle detecting and warning method includes providing a detecting and warning step for sending a warning message by a warning module disposed at the vehicle when an obstacle is detected by any one of the detectors within the detected area.