A driving assistance system includes a database configured to store numbers of preset criteria concerning various driving conditions, a sensor, configured to sense environmental data surrounding a vehicle; a thermal image capturing device, configured to capture a thermal images surrounding the vehicle; a display device; and a processor, coupled to the sensor, the thermal image capturing device and the display device. The processor compares the environmental data against the preset criteria to determine the driving condition of the vehicle. The display device automatically display thermal images to inform and provide precautions to the driver if the driving condition indicates that the driver's vision is adversely affected.