The present invention relates to an electronic flash device capable of dimming control, particularly with the objective of enhancing the dimming precision in weak light emissions. The electronic flash device of the present invention thus predicts the quantity of overrun light after stopping of the emission based on the target quantity of emission, and performs correction to advance emission stop timing in accordance with the quantity of overrun light. Here, the rate between the target quantity of emission and the quantity of full emission by the emission means (the rate of emission) is preferably obtained so that the quantity of overrun light after stopping of the emission is predicted based on the rate of emission. In split emission, the emission stop timing is preferably corrected on each chopper emission.