There is provided an imaging device which eliminates complexity in reading an image in low resolution and reading an image in high resolution and realizes prevention of decrease in frame rate. The device includes a pixel region including a plurality of pixel elements and imaging an incident light of an object as an image and a reading unit for thinning out a pixel element from the pixel region to read a thinned out image in low resolution and reading a partial image in resolution higher than the thinned out image from a partial region of the pixel region (a horizontal shift register and a vertical shift register), wherein the reading unit reads the thinned out image and the partial image from mutually different pixel elements and reads the thinned out image and the partial image as different imaging frames.