The present disclosure discloses a method and an apparatus for varying a focal length of a camera device, and a camera device capable of varying a focal length thereof. The method includes: obtaining a position where one finger of a user touches a touch screen of the camera device; obtaining an image zooming multiple according to a distance and a direction that the finger of the user slides on the touch screen of the camera device; and zooming, according to the image zooming multiple and by using the position on the touch screen of the camera device where the finger of the user touches the touch screen of the camera device as a center, an image currently taken by the camera device, so as to vary a focal length of the camera device. The apparatus includes: a first obtaining module, a second obtaining module, and a zooming module.