1. A boundary line recognition apparatus comprising: an on-vehicle camera that acquires image of an area around a vehicle and outputs image data; boundary line candidate extracting means that extracts a boundary line candidate which is present on a driving lane of the vehicle from the image data obtained by the on-vehicle camera; one or more boundary line feature calculating means that calculate likelihoods which represent degrees of probability of each of the boundary line candidates, to be a boundary line on the driving lane, extracted by the boundary line candidate extracting means; boundary line feature combining means that multiplies the likelihoods of each of the boundary line candidates obtained by the boundary line feature calculating means, and outputs the combined likelihood; and boundary line selecting means that selects the boundary line candidate having a maximum likelihood as the boundary line on the driving lane.