Provided is a photodetection device which is small in size and has excellent sensitivity. A photodetection device puts cathode terminals of photodiodes having different spectral characteristics into an open end state, and detects light intensity of a desired wavelength region according to a difference in electric charges that have been stored in those photodiodes in a given period of time. The photodiodes employ a system of storing electric charges, and hence even if a photocurrent is small, the photocurrent may be stored to obtain the electric charges required for detection, and the downsizing and high detection performance of a semiconductor device that forms the photodiodes may be achieved. Further, a wide dynamic range may be realized with an electric charge storage time being variable according to the light intensity, to intermittently drive an element required for difference detection at the time of difference detection so as to suppress electric power consumption, or to average the output so as to reduce flicker.