An adjustable lens module applied to an image projector is provided. The lens is positioned in a lens barrel situated within a lens housing mounted on a frame. The adjustable lens module includes a base plate, and a first, a second and a third positioning means. The base plate connected to the lens barrel is attached to the lens housing and mounted on the frame. The first, second and third positioning means are respectively positioned at the first, second and third corners of the base plate. The first and second corners are arranged diagonally on the base plate. At least the first and second positioning means are adjustably secured at the first and second corners respectively. By adjusting the relative position between the base plate and the first, second and third position means, a central axis of the lens is substantially parallel to or overlapped with an optical axis.