An optical lens system for taking image comprises three lens elements with refractive power, from the object side to the image side: a first lens element with positive refractive power, a second lens element with negative refractive power having at least one aspheric surface, a third lens element with negative refractive power having at least one aspheric surface, and an aperture stop located between the first lens element and the second lens element. By such arrangements, it can effectively reduce the volume and the sensitivity of the lens system.