In order to provide a laser irradiation system, a method for removing a coating, and a laser irradiation apparatus capable of efficiently removing a coating on a surface of a structure and recovering the removed substance using suction, a laser head (3) is configured from an optical system (4) for irradiating laser beam (30), a suctioning means (33) for suctioning removed matter (60) produced at the point where the laser beam (30) is directed, and an attachment (5) configured to be capable of abutting a surface (20) of a structure, the optical system (4) being operated to scan the irradiation point of the laser beam so as to draw a trajectory of a circle having a radius r1 around the optical axis of the laser beam (30) on a surface substantially perpendicular to the optical axis.