An automatic zooming method and an apparatus includes determining a contour of a subject of a preview image and a central point of the subject according to the preview image in a preview frame on a screen; when the central point of the subject overlaps a central point of the preview frame, determining a zoom parameter according to a size of the contour of the subject and a size of the preview frame, where the zoom parameter includes at least one of a to-be-adjusted focal length of a camera or a zoom factor of the preview image; and zooming the camera according to the zoom parameter.