An optical photographing lens system includes, 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 a convex object-side surface and a concave image-side surface. The second lens element has positive refractive power. The third lens element has refractive power. The fourth lens element has refractive power, wherein at least one surface of the fourth lens element is aspheric. The fifth lens element with positive refractive power has a convex image-side surface and both of the surfaces are aspheric. The sixth lens element with negative refractive power has an image-side surface changing from concave at a paraxial region to convex at a peripheral region, and both of the surfaces are aspheric.