A vehicular warning system includes an image information generating module for generating image information associated with a driver and a position of a vehicle, an operation information generating module for generating operation information associated with operation of the vehicle, and a processing module determining first and second risk values respectively with reference to the image information and the operation information, determining a risk index with reference to the first and second risk values, and generating an alert-triggering signal to be received by an alert module that generates an alert signal of one of sound, light and pictures in response to the alert-triggering signal when the risk index reaches a predetermined index threshold.