An image processing system is provided, which includes: a front monitoring device that obtains an image of a view ahead of a vehicle; a vehicle position detecting device that detects the position and orientation of the vehicle; a map database that stores road maps; a traffic indicator position estimating portion that estimates the position of a traffic indicator (23) based on the shape of a road ahead of the vehicle that has been extracted from the map database, according to the position of the vehicle that has been detected by the vehicle position detecting device; an image processing region setting portion that sets an image processing region within the image obtained by the front monitoring device based on the position of the traffic indicator that has been estimated by the traffic indicator position estimating portion; and a traffic indicator detecting portion that detects the traffic indicator from the image processing region.