1. A driving support system comprising: at least one camera for detecting lanes around a vehicle; an obstacle detecting unit for detecting an obstacle obstructing progress of the vehicle; a control device configured to correct guide lines, based on the obstacle obstructing progress of the vehicle, after the guide lines, which guide progression of the vehicle, have been recognized by the lane detecting unit, guide control the vehicle on the basis of a positional relation between the corrected guide lines determined by the correcting unit and the vehicle, and, when it is decided that the vehicle changes its route from a present lane, in which the vehicle is traveling at present, to another lane, and when an obstacle is detected on the other lane, set contact avoidance lines to avoid contact with the obstacle on the other lane from a traveling position of the present lane, correct the guide lines again so that the guide lines become inside of the contact avoidance lines, and set a control gain so that an increase in incline of yawing moment is greater at locations outside of the contact avoidance lines than at locations inside of the contact avoidance lines and outside of the guide lines.