1. An apparatus for recognizing a lane line, comprising: an edge-point extractor configured to extract edge points in an image of surroundings of a subject vehicle including a roadway ahead of the subject vehicle, the image being acquired by an image capture unit; a three-dimensional object detector configured to detect a three-dimensional object ahead of the subject vehicle; a masking area setter configured to set a masking area corresponding to the three-dimensional object detected by the three-dimensional object detector in the image captured by the image capture unit, the masking area setter being configured to, when all prescribed conditions are met, set a masking area that is partially truncated at or near a lower end of the three-dimensional object in the image as compared with a masking area set when not all of the conditions are met, the prescribed conditions including a first condition (J1) that the three-dimensional object lies in the same lane as the subject vehicle, a second condition (J2) that a width of the three-dimensional object is equal to or greater than a predetermined value, and a third condition (J3) that a distance between the three-dimensional object and the subject vehicle is equal to or less than a predetermined value; a degree-of-belief calculator configured to, for each of the edge points extracted by the edge-point extractor, calculate a degree of belief that the edge point is on the lane line, the degree of belief when the edge point is in the masking area being set less than the degree of belief when the edge point is outside the masking area; and a lane-line recognizer configured to recognize the lane line using the edge points selected based on the degrees of belief calculated for the edge points extracted by the edge-point extractor.