A six-piece optical lens system comprises, in order from the object side to the image side: a first lens element with a positive refractive power having a convex object-side surface; a second lens element with a negative refractive power having a concave image-side surface; a third lens element with a negative refractive power; a fourth lens element with a positive refractive power having a concave object-side surface; a fifth lens element with a positive refractive power having a convex image-side surface; a sixth lens element with a negative refractive power having a concave image-side surface, each of the first, second, third, fourth, fifth and sixth lens elements has at least one aspheric surface. Thereby, such a system not only can be applied to a high resolution mobile phone, but also has a wide field of view, big stop, high pixel, high resolution and low height.