The particle beam irradiation room of this invention is purported to keep within an allowable range, a positional displacement amount from a positioned state of a patient even when the patient is moved from an irradiation-room entrance to an irradiation area after positioned at other than a patient table of the irradiation area actually used at the radiation of the particle beam. The particle beam irradiation room (20) of the invention includes: an irradiation execution room (22) in which a patient table (2) having a detachable-attachable top board (5) and an actuation device (9) for actuating the top board (5) is mounted, and that is surrounded by a shielding wall (21)； a passage (23) formed in the shielding wall (21) on its side where a pre-room (25) for positioning the patient (45) relative to the top board (5) is located, in a form that allows the patient (45) positioned relative to the top board (5) to pass straight to the irradiation execution room (22) by a transport apparatus (10)； and a shielding door (24) at the irradiation-room entrance (30) located on a side of the passage (23) toward the pre-room (25), for shielding against a leakage radiation at the radiation of the particle beam so that the leakage radiation is kept at a management value or less.
