An image sensor includes a first color separation element configured to separate an incident light, the incident light being separated into a mixture of a first color light and a third color light, and separated into a second color light; and a sensor array unit including a plurality of pixels configured to sense the separated incident light, the sensor array including a first pixel region and a second pixel region that are alternately arranged in a first direction and a second direction, the second direction crossing the first direction, wherein a stack of a first light sensing layer configured to sense the first color light and a third light sensing layer configured to sense the third color light is provided in the first pixel region, and a second light sensing layer configured to sense the second color light is provided in the second pixel region.