A charged particle irradiation system comprising: an ion source for generating charged particles; an accelerator for accelerating the charged particles generated by the ion source; an irradiation device for irradiating a target with charged particles drawn from the accelerator; and a controlling apparatus configured to control operations of the ion source, the accelerator, and the irradiation device, wherein the ion source includes a plurality of kinds of ion sources (2A, 2B, 2C) that generate different ion species as the charged particles, and characterized in that the controlling apparatus includes: a current pattern memory configured to store current values to be flown in an electromagnet provided in the accelerator defined for individual ion species; and a multiple ion species irradiation controller configured to switch a current value to be flown in the electromagnet of the accelerator based on the ion source to be used and a current value with respect to the one target stored in the current pattern memory, and to control the ion source to radiate a plurality of kinds of ion species while the plurality of kinds of ion species are switched selectively. an ion source for generating charged particles; an accelerator for accelerating the charged particles generated by the ion source; an irradiation device for irradiating a target with charged particles drawn from the accelerator; and a controlling apparatus configured to control operations of the ion source, the accelerator, and the irradiation device, wherein the ion source includes a plurality of kinds of ion sources (2A, 2B, 2C) that generate different ion species as the charged particles, and characterized in that the controlling apparatus includes: a current pattern memory configured to store current values to be flown in an electromagnet provided in the accelerator defined for individual ion species; and a multiple ion species irradiation controller configured to switch a current value to be flown in the electromagnet of the accelerator based on the ion source to be used and a current value with respect to the one target stored in the current pattern memory, and to control the ion source to radiate a plurality of kinds of ion species while the plurality of kinds of ion species are switched selectively. a current pattern memory configured to store current values to be flown in an electromagnet provided in the accelerator defined for individual ion species; and a multiple ion species irradiation controller configured to switch a current value to be flown in the electromagnet of the accelerator based on the ion source to be used and a current value with respect to the one target stored in the current pattern memory, and to control the ion source to radiate a plurality of kinds of ion species while the plurality of kinds of ion species are switched selectively. to switch a current value to be flown in the electromagnet of the accelerator based on the ion source to be used and a current value with respect to the one target stored in the current pattern memory, and to control the ion source to radiate a plurality of kinds of ion species while the plurality of kinds of ion species are switched selectively.