This disclosure relates to image sensors and electronic apparatuses including the same. An image sensor including: a pixel area including shared pixels, wherein each of the shared pixels includes at least two photodiodes that form a group and share a floating diffusion (FD) area; and a transistor (TR) area adjacent to the pixel area, wherein the TR area includes transistor sets corresponding to the shared pixels, wherein, when a first shared pixel and a second shared pixel are arranged adjacent to each other in a first direction, a first TR set corresponding to the first shared pixel and a second TR set corresponding to the second shared pixel share a source region of a first selection TR.