A photographing lens assembly includes six lens elements which are, in order from an object side to an image side: a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element and a sixth lens element. The first lens element with negative refractive power has an image-side surface being concave in a paraxial region thereof. The sixth lens element has an image-side surface being concave in a paraxial region thereof, wherein the image-side surface of the sixth lens element has at least one convex critical point in an off-axis region thereof, and both an object-side surface and the image-side surface of the sixth lens element are aspheric.