A photographing lens module includes a plurality of lens elements, wherein one of the lens elements is a plastic lens element, and at least one surface of an object-side surface and an image-side surface of the plastic lens element includes an effective optical portion and a peripheral portion. The effective optical portion is aspheric. The peripheral portion surrounds the effective optical portion, and includes a plurality of strip rib structures and a plurality of light absorbing coatings. Each of the strip rib structures has a strip shape along a radial direction of an optical axis of the plastic lens element, and the strip rib structures are arranged around the effective optical portion. The light absorbing coatings are coated on the strip rib structures respectively.