Provided is a radiation irradiation device that prevents degradation of a battery resulting from a high current that flows when radiation is generated. The radiation irradiation device includes a radiation generating part that generates radiation； a battery part that supplies electric power to the radiation generating part； and an exposure switch that receives an emission instruction of the radiation from the radiation generating part. The battery part has a lithium ion battery, a capacitor connected in parallel to the lithium ion battery, a switch element that performs switching from a state where electric power is supplied from the lithium ion battery to the capacitor to a state where electric power is supplied from the capacitor to the radiation generating part. The switch element switches between the states of the electric power supply according to an instruction received in the exposure switch.
