A mobile X-ray apparatus includes: an X-ray radiation device configured to emit X-rays； a controller configured to control the X-ray radiation device； a power supply configured to supply operating power to the X-ray radiation device and the controller； and a charger configured to charge the power supply. The power supply includes a lithium ion battery including a plurality of battery cells, at least one current sensor configured to detect current of the lithium ion battery, and a battery management system (BMS) configured to detect an occurrence of an overcurrent in the lithium ion battery via the at least one current sensor in response to receiving an X-ray emission preparation signal, and to control an on-state or an off-state of a discharge current path in which a discharge current flows from the lithium ion battery to the controller and the X-ray radiation device.
