An optical image capturing system, sequentially including a first lens element, a second lens element, a third lens element and a fourth lens element from an object side to an image side, is provided. The first lens element has negative refractive power. The second through third lens elements have refractive power. The fourth lens element has positive refractive power. At least one of the image-side surface and the object-side surface of each of the four lens elements are aspheric. The optical lens elements can increase aperture value and improve the imagining quality for use in compact cameras.