In one embodiment, an MRI apparatus (20A) includes a data acquisition system (22, 24, 26, 28, 29, 40, 42, 44, 46 and 48), a charge/discharge element (BAT) and a power control unit (52 and 309). The data acquisition system acquires nuclear magnetic resonance signals from an imaging region by performing a scan. The charge/discharge element is a part of an electric power system (304, 308a, 52, BD and BAU) of the MRI apparatus, and is charged with external electric power. The power control unit controls the electric power system in such a manner that at least one unit excluding the data acquisition system is supplied with electric power from the charge/discharge element.
