A travel control method of the present invention includes: recognizing the lane in which the host vehicle is traveling; controlling the travel of the host vehicle such that the host vehicle is situated at a predetermined position relative to a boundary line of the lane; detecting an increase in the lane width of the lane in which the host vehicle is traveling; and, if determining that one of the boundary lines situated to the left and the right of the host vehicle is a dashed line, controlling the travel of the host vehicle based on the dashed boundary line.