Image diagnosis apparatus (20) generates image data of an object by using external electric power, and includes a charge/discharge element and a charge/discharge control circuit. The charge/discharge element is charged with the external electric power and supplies part of the consumed power of the image diagnosis apparatus by discharging. The charge/discharge control circuit controls charge and discharge of the charge/discharge element in such a manner that the charge/discharge element discharges in a period during which the consumed power is larger than a predetermined power amount and the charge/discharge element is charged in a period during which the consumed power is smaller than the predetermined power amount.