An image pickup device according to an embodiment includes pixels each configured to output an analog signal based on electric charges produced in a photoelectric conversion unit and a control unit configured to control a gain applied to the analog signal to be at least a first gain and a second gain greater than the first gain in accordance with a signal value of the analog signal. Each of the pixels outputs, as the analog signal, a first signal and a second signal based on electric charges produced in the photoelectric conversion unit in a first exposure period and a second exposure period shorter than the first exposure period. The control unit controls the gain applied to the analog signal by selecting one from the first gain and the second gain in accordance with the signal value, for at least one of the first signal and the second signal.