Traveling control system for vehicle

A traveling control system for vehicle, the traveling control system comprising:

• a map database configured to store map data, the map data including information regarding one or more traffic signals provided on a road along which an own vehicle travels;
• a detector configured to detect a signal state of any, of the one or more traffic signals, that is located ahead of the own vehicle;
• a traffic signal searching unit configured to search for a nearest traffic signal from the map database, the nearest traffic signal being any, of the one or more traffic signals, that is located ahead of the own vehicle and is nearest to the own vehicle;
• and
• a speed adjusting unit configured to perform, when the signal state of the nearest traffic signal searched for by the traffic signal searching unit is not detectable by the detector, adjustment of a passing speed of the own vehicle to thereby perform a passing speed decreasing operation, the passing speed being a speed at which the own vehicle passes a periphery of the nearest traffic signal, the passing speed decreasing operation including decreasing of the passing speed of the own vehicle, stopping of the own vehicle, or both.