A lane guidance system for a vehicle for guiding a vehicle to a recommended lane in which the vehicle is recommended to run out of traffic lanes included in a route from a first point to a second point through the use of an output unit mounted on the vehicle includes: a calculating unit that calculates a predicted value of an occurrence probability of sudden lane change as information indicating the occurrence probability of sudden lane change when the vehicle runs in sections corresponding to a plurality of links; a setting unit that sets the recommended lane on the basis of the predicted value; and a generating unit that generates guidance information for the recommended lane and that outputs the guidance information to the output unit.