The present invention relates to a beam therapy apparatus comprising: a main body a beam generating unit accommodated in an interior of the main body to generate a therapy beam for treating lesions in a patient a beam delivery unit accommodated in the interior of the main body to guide the beam generated by the beam generating unit from the main body to the lesions in the patient a pattern forming unit which corresponds to the lesion area in the patient and forms a pattern constituted by a plurality of divided cells to which the therapy beam from the beam delivery unit is radiated and a control unit which controls an operation of the beam delivery unit such that the therapy beam may be radiated sequentially or at random to the cells based on the shape of the pattern formed by the pattern forming unit.
