An apparatus for recognizing lane partition lines on opposite sides of a traveling lane of a vehicle based on a forward image captured by a camera mounted in the vehicle. In the apparatus, an allowable range limiter is configured to, based on a learned value of a lane width learned by a lane width learner, limit allowable ranges for the respective lane partition lines, where in the allowable ranges the respective lane partition lines are allowed to be detected in the forward image. A lane change determiner is configured to determine whether or not there is a lane change made by the vehicle. The allowable range limiter is further configured to, if it is determined by the lane change determiner that there is a lane change, enlarge at least one of the allowable ranges limited by the allowable range limiter based on the learned value of the lane width.