An image sensor including a plurality of sensing pixels, a plurality of micro-lenses disposed on the sensing pixels and a plurality of first light distributing elements disposed between the sensing pixels and the micro-lenses is provided. Each of the first light distributing elements includes a first refractive index pattern and a second refractive index pattern surrounding the first refractive index pattern. The refractive index of the first refractive index pattern is larger than the refractive index of the second refractive index pattern.