Provided is an image sensor including a color separating lens array. The image sensor includes a sensor substrate including a plurality of first photosensitive cells and a plurality of second photosensitive cells configured to sense light, and a color separating lens array including a plurality of first regions respectively corresponding to the plurality of first photosensitive cells and each including a first fine structure, and a plurality of second regions respectively corresponding to the plurality of second photosensitive cells and each including a second fine structure that is different from the first fine structure, wherein, among incident light incident on the color separating lens array, light of a first wavelength and light of a second wavelength are branched into different directions and focused on the first photosensitive cells and the second photosensitive cells.