Abstract: A lane changing system includes an inertia-detecting unit for detecting a vehicle speed, an acceleration, and body parameters of a vehicle, a geographic information unit for detecting a real-time position of the vehicle and storing road-borderline information, a visual tracker for detecting a road curvature and a relative distance and capturing a road-borderline image and a vehicle-surrounding image, a memory storing vehicle parameters, a processor, and a rotation device. The processor calculates a lateral acceleration according to the vehicle parameters, the vehicle speed, the acceleration, and the road curvature. The processor generates a steering signal when the processor determines that the relative distance is less than a first threshold, the lateral acceleration is less than a second threshold, and there is no other vehicle around the vehicle. The rotation device receives the steering signal to for making the vehicle change from an original vehicle lane to an adjacent vehicle lane.